fix: Add E2E gate job for branch protection compatibility

.github/workflows/e2e.yml

@@ -19,7 +19,6 @@ jobs:
   e2e:
     name: E2E / ${{ matrix.suite }}
     runs-on: ubuntu-24.04
-    # Only run on changeset release PRs (skipped checks count as passing for other PRs)
     if: startsWith(github.head_ref, 'changeset-release/')
     strategy:
       fail-fast: false
@@ -82,3 +81,19 @@ jobs:
           EXA_API_KEY: ${{ secrets.EXA_API_KEY }}
           OPENAI_API_KEY: ${{ secrets.OPENAI_API_KEY }}
           GOOGLE_GENERATIVE_AI_API_KEY: ${{ secrets.GOOGLE_GENERATIVE_AI_API_KEY }}
+
+  # Gate job for branch protection: required check that passes when E2E is
+  # skipped (non-release PRs) or when all matrix suites succeed.
+  e2e-status:
+    name: E2E Status
+    runs-on: ubuntu-24.04
+    if: always()
+    needs: [e2e]
+    steps:
+      - name: Check E2E result
+        run: |
+          if [[ "${{ needs.e2e.result }}" == "failure" || "${{ needs.e2e.result }}" == "cancelled" ]]; then
+            echo "E2E tests failed or were cancelled"
+            exit 1
+          fi
+          echo "E2E tests passed or were skipped"