macos: fold relaunch prompt into the warning row instead of a toast

The cut-off toast UX ("Accessibility granted. Relaunch Lan Mouse so
capture and emulat…") was unreadable in a compact window and split
the "grant" and "relaunch" flows into two disconnected surfaces. Fold
everything into the existing warning row with state-dependent content:

- AX missing:
    title    = "input capture is disabled"
    subtitle = "grant Accessibility permission to enable"
    button   = "Grant"   → opens System Settings → Accessibility

- AX granted, daemon still bailed:
    title    = "relaunch required"
    subtitle = "Accessibility granted — restart to activate capture
                and emulation"
    button   = "Relaunch" → spawns a fresh bundle via `open` after
                            a 1s delay, then quits.

- Both active: row hidden.

The emulation_status_row is kept hidden on macOS because capture and
emulation share the same TCC gate — a single row is sufficient and
two identical-looking warnings were noisy. `handle_emulation` still
exists for the non-macOS platforms where the rows are distinct.

Side effects:
- `relaunch_bundle` moved from lib.rs to macos_privacy so imp.rs can
  call it from the row button handler.
- AX watcher callback shrinks to `window.present()` +
  `refresh_capture_emulation_status()`; the toast-based dialog is
  gone along with its helper.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

lan-mouse-gtk/src/macos_privacy.rs

@@ -104,6 +104,33 @@ pub fn open_accessibility_settings() {
     open_url("x-apple.systempreferences:com.apple.preference.security?Privacy_Accessibility");
 }
 
+/// Spawn a fresh instance of the current `.app` bundle via Launch Services
+/// after a 1-second delay, so the new instance starts *after* the current
+/// process has exited — otherwise Launch Services reactivates the existing
+/// process instead of launching a fresh one, and the stale IPC socket
+/// would block the new daemon subprocess. The caller is responsible for
+/// quitting the current process (e.g. `Application::quit()`) after this.
+pub fn relaunch_bundle() {
+    // Resolve the .app bundle path from the current executable: it lives
+    // at <bundle>/Contents/MacOS/lan-mouse, so three parents up is the
+    // bundle root we hand to `open`.
+    let Ok(exe) = std::env::current_exe() else {
+        return;
+    };
+    let Some(bundle) = exe
+        .parent()
+        .and_then(std::path::Path::parent)
+        .and_then(std::path::Path::parent)
+    else {
+        return;
+    };
+
+    // Trailing `&` backgrounds the sleep+open so our shell call returns
+    // immediately; the spawned shell is adopted by launchd once we exit.
+    let cmd = format!("(sleep 1 && open {bundle:?}) &");
+    let _ = Command::new("sh").arg("-c").arg(cmd).spawn();
+}
+
 /// Make sure the app appears in System Settings → Privacy → Input Monitoring.
 ///
 /// `CGRequestListenEventAccess()` is *supposed* to register the app in the