Implemented a Zustand-based project_id store, expanded project selection/switching to persist project_id,

and centralized backend requests via api/apiFetch (including data provider updates) to inject X-Project-ID.

src/providers/data-provider/index.ts

@@ -1,7 +1,6 @@
 "use client";
 
 import dataProviderSimpleRest from "@refinedev/simple-rest";
+import { api, API_URL } from "@/lib/api";
 
-const API_URL = "https://api.fake-rest.refine.dev";
-
-export const dataProvider = dataProviderSimpleRest(API_URL);
+export const dataProvider = dataProviderSimpleRest(API_URL, api);