fix(dev): 本地 API 默认端口改为 3100 避开 Windows 保留段

Hyper-V 常保留 2960-3059，3000 会 EACCES；ensure-port-free 与 Vite 代理从 apps/api/.env 读取 PORT

apps/player/vite.config.ts

@@ -1,6 +1,9 @@
 import { defineConfig } from 'vite';
 import vue from '@vitejs/plugin-vue';
 import { resolve } from 'path';
+import { resolveApiDevTarget } from '../../scripts/dev-api-target.mjs';
+
+const apiTarget = resolveApiDevTarget();
 
 export default defineConfig({
   plugins: [vue()],
@@ -37,8 +40,8 @@ export default defineConfig({
   server: {
     port: 5173,
     proxy: {
-      '/api': { target: 'http://localhost:3000', changeOrigin: true },
-      '/uploads': { target: 'http://localhost:3000', changeOrigin: true },
+      '/api': { target: apiTarget, changeOrigin: true },
+      '/uploads': { target: apiTarget, changeOrigin: true },
     },
   },
 });