Matrix P2 (part 1): data-driven upgrade baselines from live telemetry

.github/workflows/ci.yml

@@ -201,8 +201,35 @@ jobs:
           retention-days: 14
           if-no-files-found: ignore
 
+  # Release gate: block marketplace publish until the Install/Update Matrix
+  # reports green for this tag commit. The matrix workflow (triggered by the
+  # same tag push) sets the 'Install/Update Matrix' commit status; we poll it.
+  matrix-gate:
+    runs-on: ubuntu-latest
+    if: success() && startsWith(github.ref, 'refs/tags/')
+    timeout-minutes: 60
+    steps:
+      - name: Wait for Install/Update Matrix status on this commit
+        uses: actions/github-script@v7
+        with:
+          script: |
+            const ref = context.sha;
+            // Poll up to ~50 min (100 x 30s): the matrix builds 3 platforms +
+            // runs 12 cells, which on a cold cache can exceed 30 min.
+            for (let i = 0; i < 100; i++) {
+              const { data } = await github.rest.repos.getCombinedStatusForRef({
+                owner: context.repo.owner, repo: context.repo.repo, ref });
+              const s = data.statuses.find((x) => x.context === 'Install/Update Matrix');
+              if (s && s.state === 'success') { core.info('Install/Update Matrix green'); return; }
+              if (s && s.state === 'failure') { core.setFailed('Install/Update Matrix failed — blocking release'); return; }
+              if (s && s.state === 'error') { core.setFailed('Install/Update Matrix status errored — blocking release'); return; }
+              core.info('waiting for Install/Update Matrix status...');
+              await new Promise((r) => setTimeout(r, 30000));
+            }
+            core.setFailed('Timed out waiting for Install/Update Matrix status');
+
   release-vsstudio-marketplace:
-    needs: [build, release-smoke]
+    needs: [build, release-smoke, matrix-gate]
     runs-on: ubuntu-latest
     if: success() && startsWith( github.ref, 'refs/tags/')
     strategy:
@@ -256,7 +283,7 @@ jobs:
           text: "Tag: ${{  github.ref_name }} release to Visual Studio Marketplace status: ${{ needs.release-vsstudio-marketplace.result == 'success' && 'succeeded' || 'failed' }} :${{ needs.release-vsstudio-marketplace.result == 'success' && 'tada' || 'disappointed' }}:"
 
   release-openvsx-marketplace:
-    needs: build
+    needs: [build, matrix-gate]
     runs-on: ubuntu-latest
     if: success() && startsWith( github.ref, 'refs/tags/')
     strategy: