fix(core): resolve local client url redirects and stabilize dev environment

- enforce localhost:5174 for wheel campaign client URL in local development
- lock vite dev server ports using strictPort on admin (5173) and client (5174)
- sanitize .env.example and remove hardcoded staging domain
- configure root dev orchestration and docker multi-stage build context

apps/client/vite.config.ts

@@ -10,8 +10,31 @@ export default defineConfig({
       '@lucky-wheel/shared-types': path.resolve(__dirname, '../../packages/shared-types/src/index.ts'),
     },
   },
+  build: {
+    target: 'es2020',
+    cssCodeSplit: true,
+    rollupOptions: {
+      output: {
+        manualChunks(id) {
+          if (id.includes('node_modules')) {
+            if (id.includes('vue') || id.includes('pinia') || id.includes('vue-router')) {
+              return 'vendor-vue';
+            }
+            if (id.includes('lucide') || id.includes('canvas-confetti')) {
+              return 'vendor-ui';
+            }
+          }
+          if (id.includes('/components/wheels/')) {
+            const name = id.split('/components/wheels/')[1]?.split('.')[0];
+            if (name) return `wheel-${name.toLowerCase()}`;
+          }
+        },
+      },
+    },
+  },
   server: {
     port: 5174,
+    strictPort: true,
     proxy: {
       '/api': {
         target: 'http://localhost:3000',