chore: publish Phase 2 validation output to temporary branch

Author: fajarnugraha37

.github/workflows/ci.yml

@@ -47,18 +47,16 @@ jobs:
           }
           console.log('schemas ok');
           NODE
-      - name: Commit validated source implementation
+      - name: Publish validated source commit
         id: commit
         shell: bash
-        env:
-          HEAD_BRANCH: ${{ github.event.pull_request.head.ref || github.ref_name }}
         run: |
           set -euo pipefail
           git config user.name "github-actions[bot]"
           git config user.email "41898282+github-actions[bot]@users.noreply.github.com"
           git add global-template/docgen
           git commit -m "feat: stabilize runtime and add stack-neutral quality gates"
-          git push origin "HEAD:${HEAD_BRANCH}"
+          git push origin "HEAD:agent/phase2-validated-output"
           echo "sha=$(git rev-parse HEAD)" >> "$GITHUB_OUTPUT"
 
   validate-final: