fix: replace actions/checkout@v4 with local git clone from Gitea

CI runner in China can't reach GitHub to download the checkout action.
Clone directly from internal Gitea container (http://gitea:3000) instead.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

.gitea/workflows/deploy-claude-dev-dev.yml

@@ -20,9 +20,10 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v4
-        with:
-          ref: ${{ github.sha }}
+        run: |
+          if [ ! -d .git ]; then
+            git clone --branch "${GITHUB_REF_NAME}" --depth=1 "http://gitea:3000/${GITHUB_REPOSITORY}.git" .
+          fi
 
       - name: Resolve image tags
         run: |