fix(pack): LICENSE → LICENSE.md（SkillHub 拒绝无扩展名文件）

包内 4 个无扩展名 LICENSE 会被 SkillHub 拦截：
- fmode-report-publish / fmode-deliverable / fmode-heterarchy / fmode-code-agent

打包时自动重命名为 LICENSE.md，包内无扩展名文件归零。

scripts/pack-release.mjs

@@ -51,7 +51,9 @@ function copyTree(src, dest, rel = '') {
     const relPath = rel ? `${rel}/${e.name}` : e.name;
     if (SKIP.some(re => re.test(relPath))) continue;
     const s = path.join(src, e.name);
-    const d = path.join(dest, e.name);
+    // SkillHub 拒绝无扩展名文件：LICENSE → LICENSE.md
+    const outName = e.name === 'LICENSE' ? 'LICENSE.md' : e.name;
+    const d = path.join(dest, outName);
     if (e.isDirectory()) copyTree(s, d, relPath);
     else if (e.isFile()) fs.copyFileSync(s, d);
   }