fix: sync to Gitee when workflow is triggered by tag push

Fetch origin master before pushing branch ref on tag events to avoid detached HEAD refspec errors.

Co-authored-by: Cursor <cursoragent@cursor.com>

Author: Salvatore-chen

.github/workflows/sync-gitee.yml

@@ -30,5 +30,11 @@ jobs:
       - name: Push to Gitee
         run: |
           git remote add gitee git@gitee.com:zhang-yunrui/codesign-vault.git
+
+          # Tag push checks out detached HEAD; fetch master before pushing branch ref.
+          if [ "${{ github.ref_type }}" = "tag" ]; then
+            git fetch origin master:refs/heads/master
+          fi
+
           git push gitee refs/heads/master:refs/heads/master
           git push gitee --tags

docs/DEVELOPMENT.md

@@ -169,7 +169,7 @@ ssh-keygen -t ed25519 -C "github-actions-gitee-sync" -f gitee_sync_key -N ""
 git push origin master          # → 触发 sync-gitee，同步 master 到 Gitee
 git tag v1.7.0 && git push origin v1.7.0
 # → 触发 release.yml（GitHub + Gitee Release）
-# → 触发 sync-gitee.yml（同步 tag）
+# → 触发 sync-gitee.yml（fetch master 后同步分支与 tags）
 ```
 
 ### 本地手动推送到 Gitee（可选）