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/resources/window.ui

@@ -50,7 +50,7 @@
                         <child>
                           <object class="AdwActionRow" id="capture_status_row">
                             <property name="title">input capture is disabled</property>
-                            <property name="subtitle">required for outgoing connections — click Reenable to grant permission</property>
+                            <property name="subtitle">required for outgoing and incoming connections</property>
                             <property name="icon-name">dialog-warning-symbolic</property>
                             <child>
                               <object class="GtkButton" id="input_capture_button">
@@ -76,7 +76,7 @@
                         <child>
                           <object class="AdwActionRow" id="emulation_status_row">
                             <property name="title">input emulation is disabled</property>
-                            <property name="subtitle">required for incoming connections — click Reenable to grant permission</property>
+                            <property name="subtitle">required for incoming connections</property>
                             <property name="icon-name">dialog-warning-symbolic</property>
                             <child>
                               <object class="GtkButton" id="input_emulation_button">