fix(ci): publish merge queue E2E statuses (#4370)

Signed-off-by: Evan Lezar <elezar@nvidia.com>

Author: elezar

.github/workflows/required-ci-gates.yml

@@ -280,5 +280,8 @@ jobs:
           if [ "$CONTEXT_KIND" != "merge_group" ]; then
             evaluate_workflow "OpenShell / E2E" "branch-e2e.yml" "Branch E2E Checks" "test:e2e" "Core E2E result"
             evaluate_workflow "OpenShell / GPU E2E" "branch-e2e.yml" "Branch E2E Checks" "test:e2e-gpu" "GPU E2E result"
+          else
+            post_status "OpenShell / E2E" success "Not applicable: E2E runs only on PRs" "$STATUS_TARGET_URL"
+            post_status "OpenShell / GPU E2E" success "Not applicable: GPU E2E runs only on PRs" "$STATUS_TARGET_URL"
           fi
           evaluate_workflow "OpenShell / Helm Lint" "helm-lint.yml" "Helm Lint"

CI.md

@@ -487,7 +487,7 @@ its own stable result status.
 Merge-group runs use the `merge_group` event. The event is distinct from `pull_request` and `push`, and GitHub will not report required checks for queued PRs unless the workflows include it. In this repository:
 
 - `Branch Checks` runs the standard non-E2E gates on the merge-group SHA.
-- `Branch E2E Checks` does not run for merge groups. E2E suites remain opt-in on PRs.
+- `Branch E2E Checks` does not run for merge groups. E2E suites remain opt-in on PRs. `Required CI Gates` publishes successful not-applicable statuses for both E2E contexts on merge-group events and subsequent merge-group workflow completions.
 - `Helm Lint` runs for merge groups without the PR diff optimization, because the merge-group branch is the final integration state.
 - `Trivy Changes` compares the merge-group configuration with its base and rejects new High or Critical findings.
 - `Required CI Gates` posts the same `OpenShell / ...` statuses to the merge-group SHA and does not require a `pull-request/<N>` mirror for merge-group events.