feat(#98): 검색 form 타입 생성

Author: wkdtnqls0506

src/app/(search)/_types/index.ts

@@ -0,0 +1 @@
+export type { SearchStoreFormValues } from "./searchStore.types";

src/app/(search)/_types/searchStore.types.ts

@@ -0,0 +1,3 @@
+export type SearchStoreFormValues = {
+  searchTerm: string;
+};