refactor(command-system): standardize command execution with *args/**kwargs

- Refactor exec_with_args to use *args/**kwargs instead of tuple arguments
- Add *args/**kwargs to all command execute functions for consistency
- Support multiple key bindings per command in registration
- Add character-based key binding support via get_char() in KeyMapper
- Make execute_plugin async and use asyncio.run for plugin execution
- Use MIME type from Gio content_type instead of language for ftype

src/libs/controllers/controller_manager.py

@@ -33,7 +33,9 @@ class ControllerManager(Singleton, dict):
             raise ControllerManagerException("Must pass in a 'name' and 'controller'...")
 
         if name in self.keys():
-            raise ControllerManagerException(f"Can't bind controller to registered name of '{name}'...")
+            raise ControllerManagerException(
+                f"Can't bind controller to existing registered name of '{name}'..."
+            )
 
         controller.set_controller_context( self._crete_controller_context() )