Refactor code and update environment type definitions.

- Consolidate type definitions in vite-env.d.ts
- Update TypeScript include paths

lightrag_webui/vite.config.ts

@@ -18,14 +18,14 @@ export default defineConfig({
     emptyOutDir: true
   },
   server: {
-    proxy: import.meta.env.VITE_API_PROXY === 'true' && import.meta.env.VITE_API_ENDPOINTS ? 
+    proxy: import.meta.env.VITE_API_PROXY === 'true' && import.meta.env.VITE_API_ENDPOINTS ?
       Object.fromEntries(
         import.meta.env.VITE_API_ENDPOINTS.split(',').map(endpoint => [
           endpoint,
           {
             target: import.meta.env.VITE_BACKEND_URL || 'http://localhost:9621',
             changeOrigin: true,
-            rewrite: endpoint === '/api' ? 
+            rewrite: endpoint === '/api' ?
               (path) => path.replace(/^\/api/, '') : undefined
           }
         ])