Add App Intents to enable/disable BG speech via Shortcuts

LoopFollow/Controllers/SpeakBGIntents.swift

@@ -0,0 +1,49 @@
+// LoopFollow
+// SpeakBGIntents.swift
+
+import AppIntents
+
+struct EnableSpeakBGIntent: AppIntent {
+    static var title: LocalizedStringResource = "Turn On Speak BG"
+    static var description = IntentDescription("Turns on Speak BG so LoopFollow reads glucose values aloud.")
+
+    @MainActor
+    func perform() async throws -> some IntentResult & ProvidesDialog {
+        try SpeakBGIntentSupport.set(true)
+        return .result(dialog: "Speak BG is now on.")
+    }
+}
+
+struct DisableSpeakBGIntent: AppIntent {
+    static var title: LocalizedStringResource = "Turn Off Speak BG"
+    static var description = IntentDescription("Turns off Speak BG so LoopFollow stops reading glucose values aloud.")
+
+    @MainActor
+    func perform() async throws -> some IntentResult & ProvidesDialog {
+        try SpeakBGIntentSupport.set(false)
+        return .result(dialog: "Speak BG is now off.")
+    }
+}
+
+enum SpeakBGIntentSupport {
+    /// Storage writes are memory-only during a suspected before-first-unlock
+    /// launch, so the change would be lost on hydration.
+    @MainActor
+    static func set(_ enabled: Bool) throws {
+        guard !StorageReadiness.isSuppressingWrites else {
+            throw SpeakBGIntentError.storageUnavailable
+        }
+        Storage.shared.speakBG.value = enabled
+    }
+}
+
+enum SpeakBGIntentError: Error, CustomLocalizedStringResourceConvertible {
+    case storageUnavailable
+
+    var localizedStringResource: LocalizedStringResource {
+        switch self {
+        case .storageUnavailable:
+            return "LoopFollow can't change Speak BG until your iPhone has been unlocked once after restarting."
+        }
+    }
+}

LoopFollow/LiveActivity/RestartLiveActivityIntent.swift

@@ -40,6 +40,18 @@
                 shortTitle: "Restart Live Activity",
                 systemImageName: "dot.radiowaves.left.and.right"
             )
+            AppShortcut(
+                intent: EnableSpeakBGIntent(),
+                phrases: ["Turn on Speak BG in \(.applicationName)"],
+                shortTitle: "Turn On Speak BG",
+                systemImageName: "speaker.wave.2"
+            )
+            AppShortcut(
+                intent: DisableSpeakBGIntent(),
+                phrases: ["Turn off Speak BG in \(.applicationName)"],
+                shortTitle: "Turn Off Speak BG",
+                systemImageName: "speaker.slash"
+            )
         }
     }
 #endif