fix(tools): CLI 守卫防 argv[1] 空崩溃 + check-cocos 宿主版本缺失早退

- C1: 4 个 CLI 脚本守卫加 process.argv[1] 空值短路，避免动态 import 时 pathToFileURL(undefined) 崩溃
- I1: check-cocos-version CLI 在宿主 creator.version 为 null 时报错 exit 1，避免 CI 虚假 OK
- M1: scaffold 测试收紧 UUID 正则
- 新增 cli-entry 测试覆盖动态 import 场景

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

cocoscreator_projects/scripts/check-cocos-version.mjs

@@ -16,8 +16,12 @@ export function checkVersions(hostProject, gamesDir) {
 }
 
 // CLI 入口：有不一致则退出码 1
-if (import.meta.url === pathToFileURL(process.argv[1]).href) {
+if (process.argv[1] && import.meta.url === pathToFileURL(process.argv[1]).href) {
   const { expected, mismatches } = checkVersions(HOST_PROJECT, GAMES_DIR);
+  if (expected == null) {
+    console.error('错误: 宿主工程缺少 creator.version');
+    process.exit(1);
+  }
   console.log(`宿主 Cocos 版本: ${expected}`);
   if (mismatches.length === 0) {
     console.log('OK: 所有子游戏工程版本一致。');