Implement keyboard shortcut inhibit protocol

TODO: restrict what apps can call this in some way.

src/wayland/handlers/keyboard_shortcuts_inhibit.rs

@@ -0,0 +1,22 @@
+// SPDX-License-Identifier: GPL-3.0-only
+
+use crate::state::State;
+use smithay::{
+    delegate_keyboard_shortcuts_inhibit,
+    wayland::keyboard_shortcuts_inhibit::{
+        KeyboardShortcutsInhibitHandler, KeyboardShortcutsInhibitState, KeyboardShortcutsInhibitor,
+    },
+};
+
+impl KeyboardShortcutsInhibitHandler for State {
+    fn keyboard_shortcuts_inhibit_state(&mut self) -> &mut KeyboardShortcutsInhibitState {
+        &mut self.common.keyboard_shortcuts_inhibit_state
+    }
+
+    fn new_inhibitor(&mut self, inhibitor: KeyboardShortcutsInhibitor) {
+        // TODO: Restrict what apps can inhibit shortcuts
+        inhibitor.activate();
+    }
+}
+
+delegate_keyboard_shortcuts_inhibit!(State);

src/wayland/handlers/mod.rs

@@ -5,6 +5,7 @@ pub mod compositor;
 pub mod data_device;
 pub mod dmabuf;
 pub mod export_dmabuf;
+pub mod keyboard_shortcuts_inhibit;
 pub mod layer_shell;
 pub mod output;
 pub mod output_configuration;