[commands] Check if an application command starts with bot_ or cog_

discord/ext/commands/cog.py

@@ -162,6 +162,10 @@ class CogMeta(type):
                         raise TypeError(no_bot_cog.format(base, elem))
                     commands[elem] = value
                 elif isinstance(value, (app_commands.Group, app_commands.Command)) and value.parent is None:
+                    if is_static_method:
+                        raise TypeError(f'Command in method {base}.{elem!r} must not be staticmethod.')
+                    if elem.startswith(('cog_', 'bot_')):
+                        raise TypeError(no_bot_cog.format(base, elem))
                     cog_app_commands[elem] = value
                 elif inspect.iscoroutinefunction(value):
                     try: