refactor(frontend): os.select, MkSelectのitem指定をオブジェクトによる定義に統一し、型を狭める (#16475)

* refactor(frontend): MkSelectのitem指定をオブジェクトによる定義に統一

* fix

* spdx

* fix

* fix os.select

* fix lint

* add comment

* fix

* fix: os.select対応漏れを修正

* fix

* fix

* fix: MkSelectのmodelに対する型チェックを厳格化

* fix

* fix

* fix

* Update packages/frontend/src/components/MkEmbedCodeGenDialog.vue

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

* fix

* fix types

* fix

* fix

* Update packages/frontend/src/pages/admin/roles.editor.vue

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

* fix: MkSelectに直接配列を指定している場合に正常に型が解決されるように

---------

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

packages/frontend/src/composables/use-mkselect.ts

@@ -0,0 +1,38 @@
+/*
+ * SPDX-FileCopyrightText: syuilo and misskey-project
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+import { ref } from 'vue';
+import type { Ref, MaybeRefOrGetter } from 'vue';
+import type { MkSelectItem, OptionValue, GetMkSelectValueTypesFromDef } from '@/components/MkSelect.vue';
+
+type UnwrapReadonlyItems<T> = T extends readonly (infer U)[] ? U[] : T;
+
+/** 指定したオプション定義をもとに型を狭めたrefを生成するコンポーサブル */
+export function useMkSelect<
+	const TItemsInput extends MaybeRefOrGetter<MkSelectItem[]>,
+	const TItems extends TItemsInput extends MaybeRefOrGetter<infer U> ? U : never,
+	TInitialValue extends OptionValue | void = void,
+	TItemsValue = GetMkSelectValueTypesFromDef<UnwrapReadonlyItems<TItems>>,
+	ModelType = TInitialValue extends void
+		? TItemsValue
+		: (TItemsValue | TInitialValue)
+>(opts: {
+	items: TItemsInput;
+	initialValue?: (TInitialValue | (OptionValue extends TItemsValue ? OptionValue : TInitialValue)) & (
+		TItemsValue extends TInitialValue
+			? unknown
+			: { 'Error: Type of initialValue must include all types of items': TItemsValue }
+	);
+}): {
+	def: TItemsInput;
+	model: Ref<ModelType>;
+} {
+	const model = ref(opts.initialValue ?? null);
+
+	return {
+		def: opts.items,
+		model: model as Ref<ModelType>,
+	};
+}