feat: comprehensive rewrite — push-to-talk pipeline, Typeless UI, Chinese

This is a major rewrite of OpenLessKeyboard, renamed to OSGKeyboard
and rebuilt end-to-end. 59 files changed (+3205/-1550).

Architecture
------------
- Rename project, targets, directories from OpenLess* to OSGKeyboard*
  (OpenLess / OpenLessKeyboard / OpenLessShared / OpenLessTests).
- AudioCaptureService rewritten as @unchecked Sendable class with
  OSAllocatedUnfairLock instead of an actor, so it survives Swift 6
  strict-concurrency checks while still serialising engine + converter
  state correctly.
- Single design system (Palette / Spacing / Radius / TypeStyle /
  Motion) lifted into OSGKeyboardShared so the host app and the
  keyboard extension stay in lock-step.

Push-to-talk — first-principles fix
-----------------------------------
- App Group + audio-input entitlements were stripped by Xcode's
  Automatic Signing. They are now declared in project.yml so
  'xcodegen generate' re-emits them every time. iOS Developer
  Account is untouched; only the App Group capability was added.
- State machine uses a real stored `phase` (was a derived shim
  that locked out every press after the first because
  recordStream was never nilled after the pipeline finished).
- Microphone permission is requested inside pressBegan (async
  Task) so the press flow optimistically enters .recording;
  permission denial surfaces a short error and returns to idle.
- Replaced LongPressGesture(0.15s) with a DragGesture +
  TapGesture pair separated by pressArmed, so a single tap no
  longer fires both onPressBegan and onTap simultaneously.
- Real RMS / peak level meter from the AVAudioEngine tap (was a
  pseudo-random walk); the visible waveform is now driven by
  actual audio.
- SFSpeechRecognizer(locale:) with selectable ASR locales
  (auto / zh-Hans / zh-Hant / en-US / ja-JP / ko-KR) for
  first-class Chinese / English / Japanese / Korean dictation,
  with on-device recognition when supported.
- AVAudioSession now deactivates on stop so other apps' audio
  routing is restored.

Keyboard UI — Typeless-inspired layout
---------------------------------------
- Hero area is 280 pt with a 96 pt record disc, breathing outer
  ring, and a 12-bar waveform driven by the real RMS.
- inputView.allowsSelfSizing + a heightAnchor constraint so iOS
  no longer crops the keyboard under the Spotlight bar / home
  indicator.
- Top bar: mode chip (Off / 转写 / 润色) + locale chip
  (Auto / 简体 / 繁體 / EN / 日 / 한) + status badge + ⚙.
- Bottom bar: globe / delete / 空格 / return — all 40 pt and
  balanced.
- RecordButton onPressEnded is now safe to fire from a quick
  press; pressArmed prevents double-firing.

LLM / Polishing
---------------
- LLMClient: stopped leaking the server response body in errors
  (server body is now logged at debug, never surfaced to UI);
  added a dedicated .rateLimited case for 429.
- PolishingService timeout 8s → 12s to accommodate slower
  domestic LLM providers.
- AppGroupStore.defaultSystemPrompt is now provider-aware
  (Chinese for zhipu/moonshot/qwen/deepseek, English otherwise).

Onboarding & Settings
---------------------
- Re-themed OnboardingView / HomeView / SettingsView on the
  new design system.
- ProviderPickerSection now shows 6 providers (OpenAI, DeepSeek,
  Qwen DashScope, 智谱 GLM, 月之暗面 Moonshot, Custom) with
  blurb + selected accent.
- PickerRow for Mode and ASR locale; System Prompt editor with
  reset-to-default.
- API settings page "Get an API key" used SwiftUI Link, which
  has a hit-test bug on iOS 18 that ate gestures from adjacent
  TextFields (manifested as "typing jumps to a website"). It is
  now an explicit Button + contentShape + .submitLabel(.done) on
  the fields.

Polish & tests
--------------
- LLMClientTests: 4 unit tests passing (ProviderConfig
  persistence + OpenAI request/response + HTTP error + missing
  key); test App Group renamed to the correct identifier.
- ProviderConfig.apply now captures the previous provider id
  *before* mutating, so switching providers actually resets the
  system prompt to the new default.

Build
-----
- Swift 6 strict concurrency, iOS 18.0 deployment target.
- Tested on Xcode 26 + iPhone 17 Pro simulator. A real device on
  iOS 27 beta aborts with __abort_with_payload (dispatch
  library ABI mismatch); use an iOS 18 real device or the
  iOS 26 simulator for now.

🤖 Generated with Claude Code

OSGKeyboardShared/Models/AudioBufferSnapshot.swift

@@ -0,0 +1,34 @@
+// AudioBufferSnapshot.swift
+// OSGKeyboard · Shared
+//
+// Sendable wrapper around a Float32 audio buffer's raw samples.
+// The snapshot is the only thing that crosses actor / concurrency
+// boundaries; the recognizer re-creates an `AVAudioPCMBuffer` on its
+// own side and consumes it locally (never yielding it back out).
+
+import Foundation
+import AVFoundation
+
+public struct AudioBufferSnapshot: Sendable {
+    public let samples: [Float]
+    public let sampleRate: Double
+
+    public init(samples: [Float], sampleRate: Double) {
+        self.samples = samples
+        self.sampleRate = sampleRate
+    }
+
+    /// Construct from an `AVAudioPCMBuffer` by copying out the channel data.
+    public init(buffer: AVAudioPCMBuffer) {
+        guard let channelData = buffer.floatChannelData else {
+            self.samples = []
+            self.sampleRate = buffer.format.sampleRate
+            return
+        }
+        let n = Int(buffer.frameLength)
+        var copy = [Float](repeating: 0, count: n)
+        memcpy(&copy, channelData[0], n * MemoryLayout<Float>.size)
+        self.samples = copy
+        self.sampleRate = buffer.format.sampleRate
+    }
+}

OSGKeyboardShared/Models/LLMProvider.swift

@@ -0,0 +1,87 @@
+// LLMProvider.swift
+// OSGKeyboard · Shared
+//
+// Provider preset: a known cloud LLM with sensible defaults.
+// User picks one of these on first launch, or defines a Custom one.
+
+import Foundation
+
+public struct LLMProvider: Identifiable, Codable, Hashable, Sendable {
+    public let id: String
+    public let name: String
+    public let defaultBaseURL: String
+    public let defaultModel: String
+    public let apiKeyURL: URL?
+    /// Optional short blurb shown under the provider name in the picker.
+    public let blurb: String?
+
+    public init(
+        id: String,
+        name: String,
+        defaultBaseURL: String,
+        defaultModel: String,
+        apiKeyURL: URL? = nil,
+        blurb: String? = nil
+    ) {
+        self.id = id
+        self.name = name
+        self.defaultBaseURL = defaultBaseURL
+        self.defaultModel = defaultModel
+        self.apiKeyURL = apiKeyURL
+        self.blurb = blurb
+    }
+
+    public static let presets: [LLMProvider] = [
+        .init(
+            id: "openai",
+            name: "OpenAI",
+            defaultBaseURL: "https://api.openai.com/v1",
+            defaultModel: "gpt-4o-mini",
+            apiKeyURL: URL(string: "https://platform.openai.com/api-keys"),
+            blurb: "GPT-4o mini · 多语言"
+        ),
+        .init(
+            id: "deepseek",
+            name: "DeepSeek",
+            defaultBaseURL: "https://api.deepseek.com/v1",
+            defaultModel: "deepseek-chat",
+            apiKeyURL: URL(string: "https://platform.deepseek.com/api_keys"),
+            blurb: "deepseek-chat · 中文友好"
+        ),
+        .init(
+            id: "qwen",
+            name: "Qwen (DashScope)",
+            defaultBaseURL: "https://dashscope.aliyuncs.com/compatible-mode/v1",
+            defaultModel: "qwen-plus",
+            apiKeyURL: URL(string: "https://dashscope.console.aliyun.com/apiKey"),
+            blurb: "通义千问 · OpenAI 兼容"
+        ),
+        .init(
+            id: "zhipu",
+            name: "智谱 GLM",
+            defaultBaseURL: "https://open.bigmodel.cn/api/paas/v4",
+            defaultModel: "glm-4-flash",
+            apiKeyURL: URL(string: "https://bigmodel.cn/usercenter/apikeys"),
+            blurb: "GLM-4-Flash · 中文优化"
+        ),
+        .init(
+            id: "moonshot",
+            name: "月之暗面 Moonshot",
+            defaultBaseURL: "https://api.moonshot.cn/v1",
+            defaultModel: "moonshot-v1-8k",
+            apiKeyURL: URL(string: "https://platform.moonshot.cn/console/api-keys"),
+            blurb: "Kimi · 长上下文"
+        ),
+        .init(
+            id: "custom",
+            name: "Custom (OpenAI-compatible)",
+            defaultBaseURL: "",
+            defaultModel: "",
+            blurb: "自建 / 任意 OpenAI 兼容端点"
+        )
+    ]
+
+    public static func provider(id: String) -> LLMProvider {
+        presets.first(where: { $0.id == id }) ?? .presets[0]
+    }
+}

OSGKeyboardShared/Models/LLMRequest.swift

@@ -0,0 +1,88 @@
+// LLMRequest.swift
+// OSGKeyboard · Shared
+//
+// OpenAI-compatible chat completion request/response models.
+// Compatible with OpenAI, DeepSeek, Qwen DashScope, and any provider that
+// implements POST {baseURL}/chat/completions.
+
+import Foundation
+
+public struct LLMRequest: Codable, Sendable {
+    public let model: String
+    public let messages: [Message]
+    public let temperature: Double?
+    public let maxTokens: Int?
+
+    public enum Message: Codable, Sendable {
+        case system(String)
+        case user(String)
+        case assistant(String)
+
+        private enum CodingKeys: String, CodingKey {
+            case role, content
+        }
+
+        public func encode(to encoder: Encoder) throws {
+            var c = encoder.container(keyedBy: CodingKeys.self)
+            switch self {
+            case .system(let s):
+                try c.encode("system", forKey: .role); try c.encode(s, forKey: .content)
+            case .user(let s):
+                try c.encode("user", forKey: .role); try c.encode(s, forKey: .content)
+            case .assistant(let s):
+                try c.encode("assistant", forKey: .role); try c.encode(s, forKey: .content)
+            }
+        }
+
+        public init(from decoder: Decoder) throws {
+            let c = try decoder.container(keyedBy: CodingKeys.self)
+            let role = try c.decode(String.self, forKey: .role)
+            let content = try c.decode(String.self, forKey: .content)
+            switch role {
+            case "system": self = .system(content)
+            case "user": self = .user(content)
+            case "assistant": self = .assistant(content)
+            default:
+                throw DecodingError.dataCorruptedError(forKey: .role, in: c,
+                    debugDescription: "Unknown role \(role)")
+            }
+        }
+    }
+
+    public init(
+        model: String,
+        messages: [Message],
+        temperature: Double? = 0.3,
+        maxTokens: Int? = nil
+    ) {
+        self.model = model
+        self.messages = messages
+        self.temperature = temperature
+        self.maxTokens = maxTokens
+    }
+}
+
+public struct LLMResponse: Codable, Sendable {
+    public let id: String?
+    public let choices: [Choice]
+
+    public struct Choice: Codable, Sendable {
+        public let index: Int
+        public let message: LLMRequest.Message
+        public let finishReason: String?
+
+        private enum CodingKeys: String, CodingKey {
+            case index, message
+            case finishReason = "finish_reason"
+        }
+    }
+
+    public var content: String {
+        switch choices.first?.message {
+        case .system(let s), .user(let s), .assistant(let s):
+            return s
+        case .none:
+            return ""
+        }
+    }
+}

OSGKeyboardShared/Models/ProviderConfig.swift

@@ -0,0 +1,100 @@
+// ProviderConfig.swift
+// OSGKeyboard · Shared
+//
+// User's LLM configuration. Persisted in App Group UserDefaults so both
+// the main app and keyboard extension read the same values.
+
+import Foundation
+import Combine
+
+public final class ProviderConfig: ObservableObject, @unchecked Sendable {
+    public static let shared = ProviderConfig()
+
+    private enum Key {
+        static let providerId   = "config.providerId"
+        static let baseURL      = "config.baseURL"
+        static let apiKey       = "config.apiKey"
+        static let model        = "config.model"
+        static let systemPrompt = "config.systemPrompt"
+        static let modeId       = "config.modeId"
+        static let localeId     = "config.localeId"
+    }
+
+    @Published public var providerId: String {
+        didSet { defaults.set(providerId, forKey: Key.providerId) }
+    }
+    @Published public var baseURL: String {
+        didSet { defaults.set(baseURL, forKey: Key.baseURL) }
+    }
+    @Published public var apiKey: String {
+        didSet { defaults.set(apiKey, forKey: Key.apiKey) }
+    }
+    @Published public var model: String {
+        didSet { defaults.set(model, forKey: Key.model) }
+    }
+    @Published public var systemPrompt: String {
+        didSet { defaults.set(systemPrompt, forKey: Key.systemPrompt) }
+    }
+    @Published public var modeId: String {
+        didSet { defaults.set(modeId, forKey: Key.modeId) }
+    }
+    @Published public var localeId: String {
+        didSet { defaults.set(localeId, forKey: Key.localeId) }
+    }
+
+    public var isConfigured: Bool {
+        !baseURL.isEmpty && !apiKey.isEmpty && !model.isEmpty
+    }
+
+    /// The system prompt the user *sees* in the editor — fall back to the
+    /// provider-aware default from `AppGroupStore` when nothing is set.
+    public var defaultSystemPrompt: String {
+        AppGroupStore.defaultSystemPrompt(for: providerId)
+    }
+
+    private let defaults: UserDefaults
+
+    public init(defaults: UserDefaults = AppGroup.defaults) {
+        self.defaults = defaults
+        let pid = defaults.string(forKey: Key.providerId) ?? "openai"
+        let preset = LLMProvider.provider(id: pid)
+        self.providerId   = pid
+        self.baseURL      = defaults.string(forKey: Key.baseURL)    ?? preset.defaultBaseURL
+        self.apiKey       = defaults.string(forKey: Key.apiKey)     ?? ""
+        self.model        = defaults.string(forKey: Key.model)      ?? preset.defaultModel
+        self.systemPrompt = defaults.string(forKey: Key.systemPrompt)
+            ?? AppGroupStore.defaultSystemPrompt(for: pid)
+        self.modeId       = defaults.string(forKey: Key.modeId)     ?? "polish"
+        self.localeId     = defaults.string(forKey: Key.localeId)   ?? "auto"
+    }
+
+    public func apply(preset: LLMProvider) {
+        // Capture the *previous* provider id BEFORE we mutate, so the
+        // system-prompt reset check below can compare against the actual
+        // prior default.
+        let oldId = providerId
+        providerId = preset.id
+        if !preset.defaultBaseURL.isEmpty {
+            baseURL = preset.defaultBaseURL
+        }
+        if !preset.defaultModel.isEmpty {
+            model = preset.defaultModel
+        }
+        // When switching providers, reset the system prompt to the new
+        // provider's default — otherwise the user is left editing a
+        // Chinese prompt on a US-English model.
+        if systemPrompt.isEmpty
+            || systemPrompt == AppGroupStore.defaultSystemPrompt(for: oldId) {
+            systemPrompt = AppGroupStore.defaultSystemPrompt(for: preset.id)
+        }
+    }
+
+    public func reset() {
+        providerId = "openai"
+        let preset = LLMProvider.provider(id: "openai")
+        baseURL = preset.defaultBaseURL
+        apiKey = ""
+        model = preset.defaultModel
+        systemPrompt = AppGroupStore.defaultSystemPrompt(for: "openai")
+    }
+}