refactor(flow): remove Live Activity and keep-alive mode picker

Keep voice sessions on silent low-profile PiP only, and fix custom polish style editor presentation via sheet(item:).

OSGKeyboardShared/Models/AppGroupConfiguration.swift

@@ -57,8 +57,6 @@ public struct AppGroupConfiguration: Sendable, Equatable {
         public static let settingsCloudPayloadV2 = "config.settings.cloudPayload.v2"
         /// When true, the host app auto-returns to the source app after a cold-start handoff.
         public static let flowSkipAppSwitch = "config.flowSkipAppSwitch"
-        /// Raw `FlowKeepAliveMode` value; mutually exclusive PiP vs Live Activity path.
-        public static let flowKeepAliveMode = "config.flowKeepAliveMode"
         /// Raw `FlowInactivityDuration` value; session expires after this idle window.
         public static let flowInactivityDuration = "config.flowInactivityDuration"
         /// One-shot: remap previous product defaults (30m / 10m) → 5m.
@@ -102,8 +100,6 @@ public struct AppGroupConfiguration: Sendable, Equatable {
     public var settingsICloudSyncEnabled: Bool
     /// Auto-return to the host app after `startflow` cold start (default on).
     public var flowSkipAppSwitch: Bool
-    /// PiP vs Live Activity keep-alive strategy (mutually exclusive).
-    public var flowKeepAliveMode: FlowKeepAliveMode
     /// Idle timeout before the Flow session ends; resets on each utterance.
     public var flowInactivityDuration: FlowInactivityDuration
     /// Whether local `SpeechAnalyzer` should attach the prepared custom language model.
@@ -292,9 +288,6 @@ public struct AppGroupConfiguration: Sendable, Equatable {
                 }
                 return defaults.bool(forKey: Keys.flowSkipAppSwitch)
             }(),
-            flowKeepAliveMode: FlowKeepAliveMode.fromStored(
-                defaults.string(forKey: Keys.flowKeepAliveMode)
-            ),
             flowInactivityDuration: FlowInactivityDuration.fromStored(
                 defaults.string(forKey: Keys.flowInactivityDuration)
             ),
@@ -406,7 +399,6 @@ public struct AppGroupConfiguration: Sendable, Equatable {
         defaults.set(llmThinkingEnabled, forKey: Keys.llmThinkingEnabled)
         defaults.set(activePolishStyleId, forKey: Keys.activePolishStyleId)
         defaults.set(flowSkipAppSwitch, forKey: Keys.flowSkipAppSwitch)
-        defaults.set(flowKeepAliveMode.rawValue, forKey: Keys.flowKeepAliveMode)
         defaults.set(flowInactivityDuration.rawValue, forKey: Keys.flowInactivityDuration)
         defaults.set(localASRCustomLanguageModelEnabled, forKey: Keys.localASRCustomLanguageModelEnabled)
         defaults.set(personalDictionaryICloudSyncEnabled, forKey: Keys.personalDictionaryICloudSyncEnabled)

OSGKeyboardShared/Models/FlowInactivityDuration.swift

@@ -32,18 +32,6 @@ public enum FlowInactivityDuration: String, CaseIterable, Identifiable, Sendable
         }
     }
 
-    public var labelKey: String {
-        switch self {
-        case .oneMinute: return "settings.flow.inactivity.1m"
-        case .fiveMinutes: return "settings.flow.inactivity.5m"
-        case .tenMinutes: return "settings.flow.inactivity.10m"
-        case .thirtyMinutes: return "settings.flow.inactivity.30m"
-        case .threeHours: return "settings.flow.inactivity.3h"
-        case .twelveHours: return "settings.flow.inactivity.12h"
-        case .twentyFourHours: return "settings.flow.inactivity.24h"
-        }
-    }
-
     public static func fromStored(_ raw: String?) -> FlowInactivityDuration {
         guard let raw, let value = FlowInactivityDuration(rawValue: raw) else {
             return .default

OSGKeyboardShared/Models/FlowKeepAliveMode.swift

@@ -1,39 +0,0 @@
-// FlowKeepAliveMode.swift
-// OSGKeyboard · Shared
-//
-// User-selectable Flow session keep-alive strategy (mutually exclusive).
-
-import Foundation
-
-public enum FlowKeepAliveMode: String, CaseIterable, Identifiable, Sendable, Codable {
-    /// Continuous audio capture + Live Activity.
-    case liveActivity = "liveActivity"
-    /// Picture-in-picture waveform keep-alive; mic released between utterances.
-    case pictureInPicture = "pictureInPicture"
-
-    public var id: String { rawValue }
-
-    /// Used when no valid keep-alive preference has been stored.
-    public static let `default`: FlowKeepAliveMode = .pictureInPicture
-
-    public var labelKey: String {
-        switch self {
-        case .liveActivity: return "settings.flow.keepAlive.liveActivity"
-        case .pictureInPicture: return "settings.flow.keepAlive.pictureInPicture"
-        }
-    }
-
-    public var subtitleKey: String {
-        switch self {
-        case .liveActivity: return "settings.flow.keepAlive.liveActivity.subtitle"
-        case .pictureInPicture: return "settings.flow.keepAlive.pictureInPicture.subtitle"
-        }
-    }
-
-    public static func fromStored(_ raw: String?) -> FlowKeepAliveMode {
-        guard let raw, let value = FlowKeepAliveMode(rawValue: raw) else {
-            return .default
-        }
-        return value
-    }
-}

OSGKeyboardShared/Models/ProviderConfig.swift

@@ -259,22 +259,7 @@ public final class ProviderConfig: ObservableObject, @unchecked Sendable {
         }
     }
 
-    /// PiP vs Live Activity keep-alive (mutually exclusive).
-    @Published public var flowKeepAliveMode: FlowKeepAliveMode {
-        didSet {
-            guard !isApplyingConfiguration, flowKeepAliveMode != configuration.flowKeepAliveMode else { return }
-            configuration.flowKeepAliveMode = flowKeepAliveMode
-            if flowKeepAliveMode == .pictureInPicture {
-                configuration.flowSkipAppSwitch = true
-                if flowSkipAppSwitch != true {
-                    flowSkipAppSwitch = true
-                }
-            }
-            persistConfiguration()
-        }
-    }
-
-    /// Idle window before an active Flow session expires; Live Activity mode only.
+    /// Retained for storage compatibility; persistent PiP sessions do not expire from inactivity.
     @Published public var flowInactivityDuration: FlowInactivityDuration {
         didSet {
             guard !isApplyingConfiguration,
@@ -406,7 +391,6 @@ public final class ProviderConfig: ObservableObject, @unchecked Sendable {
         polishIntensity = configuration.polishIntensity
         llmThinkingEnabled = configuration.llmThinkingEnabled
         flowSkipAppSwitch = configuration.flowSkipAppSwitch
-        flowKeepAliveMode = configuration.flowKeepAliveMode
         flowInactivityDuration = configuration.flowInactivityDuration
         localASRCustomLanguageModelEnabled = configuration.localASRCustomLanguageModelEnabled
         isSyncingProviderAPIKey = true
@@ -498,7 +482,6 @@ public final class ProviderConfig: ObservableObject, @unchecked Sendable {
         polishIntensity = fresh.polishIntensity
         llmThinkingEnabled = fresh.llmThinkingEnabled
         flowSkipAppSwitch = fresh.flowSkipAppSwitch
-        flowKeepAliveMode = fresh.flowKeepAliveMode
         flowInactivityDuration = fresh.flowInactivityDuration
         localASRCustomLanguageModelEnabled = fresh.localASRCustomLanguageModelEnabled
         isSyncingProviderAPIKey = true

OSGKeyboardShared/Models/SyncedAppSettingsV2.swift

@@ -31,7 +31,6 @@ public struct SyncedAppSettingsV2: Codable, Equatable, Sendable {
     public var activePolishStyleId: SyncedField<String>
     public var llmThinkingEnabled: SyncedField<Bool>
     public var flowSkipAppSwitch: SyncedField<Bool>
-    public var flowKeepAliveMode: SyncedField<FlowKeepAliveMode>
     public var flowInactivityDuration: SyncedField<FlowInactivityDuration>
 
     public init(
@@ -55,7 +54,6 @@ public struct SyncedAppSettingsV2: Codable, Equatable, Sendable {
         activePolishStyleId: SyncedField<String>,
         llmThinkingEnabled: SyncedField<Bool>,
         flowSkipAppSwitch: SyncedField<Bool>,
-        flowKeepAliveMode: SyncedField<FlowKeepAliveMode>,
         flowInactivityDuration: SyncedField<FlowInactivityDuration>
     ) {
         self.schemaVersion = schemaVersion
@@ -82,7 +80,6 @@ public struct SyncedAppSettingsV2: Codable, Equatable, Sendable {
         self.activePolishStyleId = activePolishStyleId
         self.llmThinkingEnabled = llmThinkingEnabled
         self.flowSkipAppSwitch = flowSkipAppSwitch
-        self.flowKeepAliveMode = flowKeepAliveMode
         self.flowInactivityDuration = flowInactivityDuration
     }
 
@@ -107,10 +104,13 @@ public struct SyncedAppSettingsV2: Codable, Equatable, Sendable {
         case activePolishStyleId
         case llmThinkingEnabled
         case flowSkipAppSwitch
-        case flowKeepAliveMode
         case flowInactivityDuration
     }
 
+    private enum LegacyCodingKeys: String, CodingKey {
+        case flowKeepAliveMode
+    }
+
     public init(from decoder: Decoder) throws {
         let container = try decoder.container(keyedBy: CodingKeys.self)
         schemaVersion = try container.decode(Int.self, forKey: .schemaVersion)
@@ -167,18 +167,15 @@ public struct SyncedAppSettingsV2: Codable, Equatable, Sendable {
             deviceID: keyboardHapticIntensity.deviceID
         )
         flowSkipAppSwitch = try container.decode(SyncedField<Bool>.self, forKey: .flowSkipAppSwitch)
-        flowKeepAliveMode = try container.decodeIfPresent(
-            SyncedField<FlowKeepAliveMode>.self,
-            forKey: .flowKeepAliveMode
-        ) ?? SyncedField(
-            value: .liveActivity,
-            updatedAt: flowSkipAppSwitch.updatedAt,
-            deviceID: flowSkipAppSwitch.deviceID
-        )
         flowInactivityDuration = try container.decode(
             SyncedField<FlowInactivityDuration>.self,
             forKey: .flowInactivityDuration
         )
+        let legacyContainer = try decoder.container(keyedBy: LegacyCodingKeys.self)
+        _ = try legacyContainer.decodeIfPresent(
+            SyncedField<String>.self,
+            forKey: .flowKeepAliveMode
+        )
 
         if let asrProvider = try container.decodeIfPresent(SyncedField<String>.self, forKey: .asrProviderId) {
             asrProviderId = asrProvider
@@ -224,7 +221,6 @@ public struct SyncedAppSettingsV2: Codable, Equatable, Sendable {
             activePolishStyleId.updatedAt,
             llmThinkingEnabled.updatedAt,
             flowSkipAppSwitch.updatedAt,
-            flowKeepAliveMode.updatedAt,
             flowInactivityDuration.updatedAt,
         ].max() ?? .distantPast
     }
@@ -264,7 +260,6 @@ public extension SyncedAppSettingsV2 {
             activePolishStyleId: field(configuration.activePolishStyleId),
             llmThinkingEnabled: field(configuration.llmThinkingEnabled),
             flowSkipAppSwitch: field(configuration.flowSkipAppSwitch),
-            flowKeepAliveMode: field(configuration.flowKeepAliveMode),
             flowInactivityDuration: field(configuration.flowInactivityDuration)
         )
     }
@@ -296,7 +291,6 @@ public extension SyncedAppSettingsV2 {
             activePolishStyleId: field(PolishStylePackCatalog.defaultID),
             llmThinkingEnabled: field(false),
             flowSkipAppSwitch: field(legacy.flowSkipAppSwitch),
-            flowKeepAliveMode: field(.liveActivity),
             flowInactivityDuration: field(legacy.flowInactivityDuration)
         )
     }
@@ -340,7 +334,6 @@ public extension SyncedAppSettingsV2 {
             ),
             llmThinkingEnabled: .merge(local: local.llmThinkingEnabled, remote: remote.llmThinkingEnabled),
             flowSkipAppSwitch: .merge(local: local.flowSkipAppSwitch, remote: remote.flowSkipAppSwitch),
-            flowKeepAliveMode: .merge(local: local.flowKeepAliveMode, remote: remote.flowKeepAliveMode),
             flowInactivityDuration: .merge(
                 local: local.flowInactivityDuration,
                 remote: remote.flowInactivityDuration
@@ -368,7 +361,6 @@ public extension SyncedAppSettingsV2 {
         configuration.activePolishStyleId = activePolishStyleId.value
         configuration.llmThinkingEnabled = llmThinkingEnabled.value
         configuration.flowSkipAppSwitch = flowSkipAppSwitch.value
-        configuration.flowKeepAliveMode = flowKeepAliveMode.value
         configuration.flowInactivityDuration = flowInactivityDuration.value
     }
 
@@ -398,7 +390,6 @@ public extension SyncedAppSettingsV2 {
         patch(&copy.activePolishStyleId, value: configuration.activePolishStyleId)
         patch(&copy.llmThinkingEnabled, value: configuration.llmThinkingEnabled)
         patch(&copy.flowSkipAppSwitch, value: configuration.flowSkipAppSwitch)
-        patch(&copy.flowKeepAliveMode, value: configuration.flowKeepAliveMode)
         patch(&copy.flowInactivityDuration, value: configuration.flowInactivityDuration)
         return copy
     }
@@ -431,7 +422,6 @@ public extension SyncedAppSettingsV2 {
         touch(&copy.activePolishStyleId, value: configuration.activePolishStyleId)
         touch(&copy.llmThinkingEnabled, value: configuration.llmThinkingEnabled)
         touch(&copy.flowSkipAppSwitch, value: configuration.flowSkipAppSwitch)
-        touch(&copy.flowKeepAliveMode, value: configuration.flowKeepAliveMode)
         touch(&copy.flowInactivityDuration, value: configuration.flowInactivityDuration)
         return copy
     }

OSGKeyboardShared/Services/FlowKeyboardPolicies.swift

@@ -17,7 +17,7 @@ public enum FlowKeyboardHostWarming {
     /// Keep the mic green after the session has already proven ready.
     ///
     /// Inter-utterance PiP flaps (mic release, ack lag, brief `reason=.starting`)
-    /// used to flash yellow「正在启动画中画」even though Picture in Picture was
+    /// used to flash yellow「正在启动…」even though the keep-alive surface was
     /// already running. Hold ready through those windows; real cold starts still
     /// go through `isHostWarming` while `sessionProvenReady` is false.
     public static func shouldHoldReady(

OSGKeyboardShared/Services/FlowSessionBridge.swift

@@ -405,9 +405,8 @@ public enum FlowSessionBridge {
             // a permanent orange `preparingSession` state.
             clearHostReady(defaults: store, notify: false)
         }
-        if let expires = snapshot.sessionExpiresAt {
-            store.set(expires, forKey: FlowSessionKeys.flowSessionExpires)
-        }
+        // PiP sessions are persistent; clear expiry left by older Live Activity builds.
+        store.removeObject(forKey: FlowSessionKeys.flowSessionExpires)
         // Only a genuinely live host — ready, or actively serving an
         // utterance — may refresh the heartbeat here. A host stuck in a
         // failed cold start would otherwise keep "reviving" itself on every
@@ -430,20 +429,7 @@ public enum FlowSessionBridge {
 
     // MARK: - Session lifecycle (host app)
 
-    public static func markSessionActive(
-        duration: TimeInterval? = nil,
-        sessionId: UUID? = nil,
-        defaults: UserDefaults? = nil
-    ) {
-        let store = resolvedDefaults(defaults)
-        if FlowSessionPolicy.usesInactivityExpiry(defaults: store) {
-            markSessionActiveWithExpiry(duration: duration, sessionId: sessionId, defaults: store)
-        } else {
-            markSessionActivePersistent(sessionId: sessionId, defaults: store)
-        }
-    }
-
-    /// PiP keep-alive: session stays valid until explicit teardown (no idle expiry).
+    /// PiP keep-alive: session stays valid until explicit teardown.
     public static func markSessionActivePersistent(
         sessionId: UUID? = nil,
         defaults: UserDefaults? = nil
@@ -480,44 +466,6 @@ public enum FlowSessionBridge {
         flush(store)
     }
 
-    private static func markSessionActiveWithExpiry(
-        duration: TimeInterval? = nil,
-        sessionId: UUID? = nil,
-        defaults: UserDefaults
-    ) {
-        let resolvedDuration = duration ?? FlowSessionPolicy.sessionDuration(defaults: defaults)
-        let now = Date().timeIntervalSince1970
-        let expires = now + resolvedDuration
-        defaults.set(true, forKey: FlowSessionKeys.flowSessionActive)
-        defaults.set(expires, forKey: FlowSessionKeys.flowSessionExpires)
-        defaults.set(now, forKey: FlowSessionKeys.lastActivityAt)
-        writeHeartbeat(defaults: defaults)
-        clearTranscription(defaults: defaults)
-        defaults.removeObject(forKey: FlowSessionKeys.flowCommandPayload)
-        defaults.removeObject(forKey: FlowSessionKeys.flowCommandJournalPayload)
-        defaults.removeObject(forKey: FlowSessionKeys.flowResultPayload)
-        defaults.removeObject(forKey: FlowSessionKeys.flowAckPayload)
-        defaults.removeObject(forKey: FlowSessionKeys.pendingKeyboardUtteranceId)
-        if let sessionId {
-            let snapshot = FlowReadySnapshot(
-                sessionId: sessionId,
-                ready: false,
-                reason: .starting,
-                heartbeatAt: now,
-                engineMode: AppGroupConfiguration.load(fromAvailable: defaults).engineMode,
-                localeId: AppGroupConfiguration.load(fromAvailable: defaults).localeId,
-                sessionExpiresAt: expires,
-                hostGeneration: defaults.string(forKey: FlowSessionKeys.hostGeneration)
-            )
-            if let data = encode(snapshot) {
-                defaults.set(data, forKey: FlowSessionKeys.flowReadyPayload)
-            }
-        } else {
-            defaults.removeObject(forKey: FlowSessionKeys.flowReadyPayload)
-        }
-        flush(defaults)
-    }
-
     public static func markSessionInactive(defaults: UserDefaults? = nil) {
         let store = resolvedDefaults(defaults)
         store.set(false, forKey: FlowSessionKeys.flowSessionActive)
@@ -544,31 +492,6 @@ public enum FlowSessionBridge {
         flush(store)
     }
 
-    public static func extendSession(
-        by duration: TimeInterval? = nil,
-        defaults: UserDefaults? = nil
-    ) {
-        let store = resolvedDefaults(defaults)
-        guard FlowSessionPolicy.usesInactivityExpiry(defaults: store) else { return }
-        let resolvedDuration = duration ?? FlowSessionPolicy.sessionDuration(defaults: store)
-        let expires = Date().timeIntervalSince1970 + resolvedDuration
-        store.set(true, forKey: FlowSessionKeys.flowSessionActive)
-        store.set(expires, forKey: FlowSessionKeys.flowSessionExpires)
-        flush(store)
-    }
-
-    /// Resets the inactivity timer after utterance completion or explicit activity.
-    public static func touchLastActivity(defaults: UserDefaults? = nil) {
-        let store = resolvedDefaults(defaults)
-        guard FlowSessionPolicy.usesInactivityExpiry(defaults: store) else { return }
-        let now = Date().timeIntervalSince1970
-        let duration = FlowSessionPolicy.sessionDuration(defaults: store)
-        store.set(now, forKey: FlowSessionKeys.lastActivityAt)
-        store.set(now + duration, forKey: FlowSessionKeys.flowSessionExpires)
-        store.set(true, forKey: FlowSessionKeys.flowSessionActive)
-        flush(store)
-    }
-
     // MARK: - Host return (scheme D)
 
     public static func setPendingHostBundleId(_ bundleId: String?, defaults: UserDefaults? = nil) {
@@ -592,18 +515,11 @@ public enum FlowSessionBridge {
 
     // MARK: - Session validity (keyboard)
 
-    /// True when the App Group session contract is still valid (not expired).
+    /// True while the persistent PiP session contract is active.
     /// Does **not** mean the host can accept utterances — use `isHostReady()`.
     public static func isSessionActive(defaults: UserDefaults? = nil) -> Bool {
         let store = resolvedDefaults(defaults)
-        guard store.bool(forKey: FlowSessionKeys.flowSessionActive) else { return false }
-
-        if !FlowSessionPolicy.usesInactivityExpiry(defaults: store) {
-            return true
-        }
-
-        let expires = store.double(forKey: FlowSessionKeys.flowSessionExpires)
-        return expires > Date().timeIntervalSince1970
+        return store.bool(forKey: FlowSessionKeys.flowSessionActive)
     }
 
     /// Seconds since the host last wrote `flowHeartbeat`; nil when never written.
@@ -800,19 +716,6 @@ public enum FlowSessionBridge {
         return true
     }
 
-    public static func sessionExpiresAt(defaults: UserDefaults? = nil) -> TimeInterval? {
-        let store = resolvedDefaults(defaults)
-        let expires = store.double(forKey: FlowSessionKeys.flowSessionExpires)
-        return expires > 0 ? expires : nil
-    }
-
-    /// Seconds until session expiry; nil when expired or never started.
-    public static func remainingSessionDuration(defaults: UserDefaults? = nil) -> TimeInterval? {
-        guard let expires = sessionExpiresAt(defaults: defaults) else { return nil }
-        let remaining = expires - Date().timeIntervalSince1970
-        return remaining > 0 ? remaining : nil
-    }
-
     // MARK: - Recording signals (keyboard → host)
 
     public static func setRecordingState(

OSGKeyboardShared/Services/FlowSessionPolicy.swift

@@ -25,18 +25,6 @@ public enum FlowSessionPolicy {
         inactivityDuration(defaults: defaults).timeInterval
     }
 
-    public static func keepAliveMode(defaults: UserDefaults? = nil) -> FlowKeepAliveMode {
-        let store = resolvedDefaults(defaults)
-        return FlowKeepAliveMode.fromStored(
-            store.string(forKey: AppGroupConfiguration.Keys.flowKeepAliveMode)
-        )
-    }
-
-    /// PiP sessions have no inactivity expiry; only the Live Activity path times out.
-    public static func usesInactivityExpiry(defaults: UserDefaults? = nil) -> Bool {
-        keepAliveMode(defaults: defaults) == .liveActivity
-    }
-
     private static func resolvedDefaults(_ defaults: UserDefaults?) -> UserDefaults {
         if let defaults { return defaults }
         guard let available = AppGroup.defaultsIfAvailable else {

OSGKeyboardShared/Views/FlowDebugPanel.swift

@@ -36,15 +36,8 @@ public enum FlowDebugAppGroupSnapshot {
             }
             return String(g.prefix(8))
         }()
-        let expires: String = {
-            guard let ts = FlowSessionBridge.sessionExpiresAt(defaults: defaults) else { return "nil" }
-            let remaining = ts - Date().timeIntervalSince1970
-            return String(format: "%.0fs", remaining)
-        }()
-
         return [
             FlowDebugRow("sessionActive", FlowSessionBridge.isSessionActive(defaults: defaults) ? "1" : "0"),
-            FlowDebugRow("expiresIn", expires),
             FlowDebugRow("hostReachable", FlowSessionBridge.isHostReachable(defaults: defaults) ? "1" : "0"),
             FlowDebugRow("hostReady", FlowSessionBridge.isHostReady(defaults: defaults) ? "1" : "0"),
             FlowDebugRow("hostStale", FlowSessionBridge.isHostStale(defaults: defaults) ? "1" : "0"),