fix: grab keyboard focus on map instead of realize (v0.7.4)

Layer-shell keyboard grab is only confirmed by the compositor at map
time. The previous realize-time grab_focus() could fire before the
compositor assigned keyboard input, causing intermittent input loss.

src/greeter.rs

@@ -553,6 +553,18 @@ pub fn create_greeter_window(
     ));
     window.add_controller(key_controller);
 
+    // Grab keyboard focus after map — layer-shell keyboard grab is only
+    // confirmed by the compositor at map time, not at realize time.
+    window.connect_map(clone!(
+        #[weak]
+        password_entry,
+        move |_| {
+            glib::idle_add_local_once(move || {
+                password_entry.grab_focus();
+            });
+        }
+    ));
+
     // Defer initial user selection until realized (for correct theme colors)
     window.connect_realize(clone!(
         #[strong]