feat: skip fixer job if fix already exists

Author: kevinwang5658

.github/workflows/claude-fixer.yml

@@ -19,8 +19,27 @@ jobs:
             echo "runner=ubuntu-latest" >> $GITHUB_OUTPUT
           fi
 
-  fix-on-failure:
+  check-existing-pr:
+    runs-on: ubuntu-latest
     needs: determine-runner
+    outputs:
+      skip: ${{ steps.check.outputs.skip }}
+    steps:
+      - id: check
+        env:
+          GH_TOKEN: ${{ github.token }}
+        run: |
+          BRANCH="${{ github.event.workflow_run.head_branch }}"
+          COUNT=$(gh pr list --repo "$GITHUB_REPOSITORY" --head "fix/claude-auto-" --base "$BRANCH" --state open --json number --jq 'length')
+          if [ "${COUNT:-0}" -gt 0 ]; then
+            echo "skip=true" >> $GITHUB_OUTPUT
+          else
+            echo "skip=false" >> $GITHUB_OUTPUT
+          fi
+
+  fix-on-failure:
+    needs: [determine-runner, check-existing-pr]
+    if: needs.check-existing-pr.outputs.skip == 'false'
     runs-on: ${{ needs.determine-runner.outputs.runner }}
     permissions:
       contents: write