feat: add talk mode across nodes

apps/macos/Sources/Clawdis/TalkModeController.swift

@@ -0,0 +1,42 @@
+import Observation
+import OSLog
+
+@MainActor
+@Observable
+final class TalkModeController {
+    static let shared = TalkModeController()
+
+    private let logger = Logger(subsystem: "com.steipete.clawdis", category: "talk.controller")
+
+    func setEnabled(_ enabled: Bool) async {
+        self.logger.info("talk enabled=\(enabled)")
+        if enabled {
+            TalkOverlayController.shared.present()
+        } else {
+            TalkOverlayController.shared.dismiss()
+        }
+        await TalkModeRuntime.shared.setEnabled(enabled)
+    }
+
+    func updatePhase(_ phase: TalkModePhase) {
+        TalkOverlayController.shared.updatePhase(phase)
+    }
+
+    func updateLevel(_ level: Double) {
+        TalkOverlayController.shared.updateLevel(level)
+    }
+
+    func stopSpeaking(reason: TalkStopReason = .userTap) {
+        Task { await TalkModeRuntime.shared.stopSpeaking(reason: reason) }
+    }
+
+    func exitTalkMode() {
+        Task { await AppStateStore.shared.setTalkEnabled(false) }
+    }
+}
+
+enum TalkStopReason {
+    case userTap
+    case speech
+    case manual
+}