refactor(frontend): Formまわりの型強化 (#16260)

* refactor(frontend): Formまわりの型強化

* fix

* avoid non-null assertion and add null check for safety

* refactor

* avoid non-null assertion and add null check for safety

* Update clip.vue

---------

Co-authored-by: syuilo <4439005+syuilo@users.noreply.github.com>

packages/frontend/src/pages/my-clips/index.vue

@@ -64,6 +64,7 @@ async function create() {
 			default: false,
 		},
 	});
+
 	if (canceled) return;
 
 	os.apiWithDialog('clips/create', result);