fix(web): support LAN development access

web/.env.example

@@ -1 +1,5 @@
-VITE_API_BASE_URL=http://localhost:5300
+# Leave empty in development to use Vite's same-origin proxy. This keeps API,
+# login, and WebSocket requests working when the UI is opened from another
+# device on the local network.
+VITE_API_BASE_URL=
+VITE_API_PROXY_TARGET=http://127.0.0.1:5300

web/vite.config.ts

@@ -1,8 +1,12 @@
-import { defineConfig } from 'vite';
+import { defineConfig, loadEnv } from 'vite';
 import react from '@vitejs/plugin-react';
 import path from 'path';
 
-export default defineConfig({
+export default defineConfig(({ mode }) => {
+  const env = loadEnv(mode, process.cwd(), '');
+  const apiProxyTarget = env.VITE_API_PROXY_TARGET || 'http://127.0.0.1:5300';
+
+  return {
     plugins: [react()],
     resolve: {
       alias: {
@@ -10,9 +14,22 @@ export default defineConfig({
       },
     },
     server: {
+      host: '0.0.0.0',
       port: 3000,
+      proxy: {
+        '/api': {
+          target: apiProxyTarget,
+          changeOrigin: true,
+          ws: true,
+        },
+        '/mcp': {
+          target: apiProxyTarget,
+          changeOrigin: true,
+        },
+      },
     },
     build: {
       outDir: 'dist',
     },
+  };
 });