feat: add AppSettings

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

Sources/SstData/AppSettings.swift

@@ -0,0 +1,45 @@
+import Combine
+import Foundation
+
+/// User preferences, persisted in UserDefaults as soon as a value changes.
+public final class AppSettings: ObservableObject {
+    public static let defaultModelVariant = "large-v3-v20240930_turbo"
+
+    enum Key {
+        static let hotkey = "hotkeyID"
+        static let model = "modelVariant"
+        static let keepHistory = "keepHistory"
+        static let usePriming = "usePriming"
+        static let useCorrection = "useCorrection"
+    }
+
+    private let defaults: UserDefaults
+
+    /// `HotkeyBinding.id` of the key that has to be held.
+    @Published public var hotkeyID: String {
+        didSet { defaults.set(hotkeyID, forKey: Key.hotkey) }
+    }
+    @Published public var modelVariant: String {
+        didSet { defaults.set(modelVariant, forKey: Key.model) }
+    }
+    @Published public var keepHistory: Bool {
+        didSet { defaults.set(keepHistory, forKey: Key.keepHistory) }
+    }
+    /// Give the speech engine the dictionary words as context.
+    @Published public var usePriming: Bool {
+        didSet { defaults.set(usePriming, forKey: Key.usePriming) }
+    }
+    /// Apply the dictionary corrections after transcription.
+    @Published public var useCorrection: Bool {
+        didSet { defaults.set(useCorrection, forKey: Key.useCorrection) }
+    }
+
+    public init(defaults: UserDefaults = .standard) {
+        self.defaults = defaults
+        hotkeyID = defaults.string(forKey: Key.hotkey) ?? "fn"
+        modelVariant = defaults.string(forKey: Key.model) ?? Self.defaultModelVariant
+        keepHistory = defaults.object(forKey: Key.keepHistory) as? Bool ?? true
+        usePriming = defaults.object(forKey: Key.usePriming) as? Bool ?? true
+        useCorrection = defaults.object(forKey: Key.useCorrection) as? Bool ?? true
+    }
+}