fix(api): align API layer with backend response formats

- wallet: parse {balance: string} response
- favorites: addFavorite returns void (EmptyResp)
- services: handle paginated response from listServicesByPlayer
- files: use query param ?key= instead of path param /:id
- search: remove unsupported selectedGames/minRating params

lib/api/favorites.ts

@@ -39,8 +39,8 @@ export async function isFavorited(
 export async function addFavorite(input: {
   targetType: "player" | "shop"
   targetId: string
-}): Promise<Favorite> {
-  return await httpJson<Favorite>("/api/v1/favorites", {
+}): Promise<void> {
+  await httpJson<unknown>("/api/v1/favorites", {
     method: "POST",
     json: input,
     cache: "no-store",