[JJC-20260618-005-D] P1/P2 cleanup: structured errors, privacy audit, timeout SSOT, view-model tests

13 items, 555-line diff, build + 15/15 tests green.

ARCH-A3: Phase.error now carries ErrorKind (micDenied/speechDenied/asr/llm/
appGroupUnavailable/unknown) so the UI can pick icons/copy without parsing
free-form strings. Phase.ErrorKind, Phase, LLMError all Equatable.

ARCH-A4: Every TextField in APISettingsCard gets .keyboardType(.asciiCapable)
to defeat SwiftUI's iOS 18 system-keyboard hand-off that auto-suggests
Chinese/emoji and corrupts API keys / URLs / model names.

ARCH-A5 + DOC-3: PrivacyInfo.xcprivacy audited for honesty. Removed three
declared-but-unused APIs (FileTimestamp / DiskSpace / SystemBootTime) and
added ActiveKeyboards (DDA9.1) to the extension (it actually calls
advanceToNextInputMode in the tap path). Main App now declares only
UserDefaults (CA92.1). CHANGELOG updated.

ARCH-A6: Extracted PermissionManager (mic+speech permission flow, iOS 17
branching) and AppGroupPersistor (App Group load/persist) from the God
Object. KeyboardViewController drops 515 → 459 lines. KeyboardPipelineController
left in-place per risk plan — pressBegan state machine is too race-sensitive
to refactor in this pass.

RED-2: Deleted unused Theme enum (no call sites).
RED-3: Deleted unused cardStyle() alias (no call sites).
RED-7: Single source of truth for LLM timeout — LLMClient.requestTimeout +
LLMClientFactory.defaultRequestTimeout; PolishingService derives timeout from
defaultRequestTimeout+1 instead of hardcoding 15.
RED-8: ASRService.transcribe now emits .capability(onDeviceSupported:) as
first event per session; StatusBadge shows REC ⚠️ when the locale fell
back to cloud. New @Published var onDeviceSupported on State.

TEST-1: testPolishThrowsOnTransportTimeout now actually exercises
cancellation: StubURLProtocol delays response 5s, client.polish is
cancelled via Task.cancel(), test asserts the client throws .cancelled /
.transport / .decoding (was: silently passed).

TEST-2: New testPolisherSkipsNetworkWhenModeOff — PolishingService now
short-circuits when modeId == 'off' and returns trimmed input without
invoking LLMClient (proved via injected CountingLLMClient). Service was
moved to OSGKeyboardShared to be reachable from the test target.

TEST-3: KeyboardState (formerly KeyboardViewController.State) extracted
into OSGKeyboardShared so tests can @testable-import it. 5 phase/mode
tests in new KeyboardStateTests. Typealias preserves the old name.

TEST-4: New OSGKeyboardExtTests target with 6 tests covering State
initial values, phase transitions, structured-error round-trip, mode
switching, and InputMode rawValue round-trip.

OSGKeyboardExt/Services/ASRService.swift

@@ -35,6 +35,11 @@ public protocol ASRService: Sendable {
 }
 
 public enum ASREvent: Sendable, Equatable {
+    /// Emitted exactly once at the start of every `transcribe` call, so
+    /// the UI can flag non-on-device locales (e.g. ja-JP on devices that
+    /// only ship on-device ASR for en/zh). The ASR session continues
+    /// either way — we fall back to cloud automatically.
+    case capability(onDeviceSupported: Bool)
     case partial(String)
     case final(String)
     case error(String)
@@ -73,11 +78,16 @@ final class AppleSpeechASR: ASRService, @unchecked Sendable {
             let request = SFSpeechAudioBufferRecognitionRequest()
             request.shouldReportPartialResults = true
             request.requiresOnDeviceRecognition = recognizer.supportsOnDeviceRecognition
-            if !recognizer.supportsOnDeviceRecognition {
+            let onDeviceSupported = recognizer.supportsOnDeviceRecognition
+            if !onDeviceSupported {
                 #if DEBUG
                 print("⚠️ 设备不支持 \(locale.identifier) 端侧 ASR, 回退云端。")
                 #endif
             }
+            // Tell the UI about the capability *before* any partials so
+            // the StatusBadge can light up the cloud-fallback indicator
+            // as soon as the user presses the mic.
+            continuation.yield(.capability(onDeviceSupported: onDeviceSupported))
 
             let task = recognizer.recognitionTask(with: request) { result, error in
                 if let error {