ci: make standalone playwright manual and document e2e gating

Author: stefanstidlffg

.github/workflows/docker-publish.yml

@@ -24,6 +24,8 @@ env:
   IMAGE_NAME: ${{ github.repository }}
 
 jobs:
+  # Keep e2e in this workflow so Docker image build/push is hard-gated by test success.
+  # Do not move automatic e2e back to playwright.yml, otherwise master pushes run duplicate e2e jobs.
   e2e:
     runs-on: ubuntu-latest
     timeout-minutes: 45

.github/workflows/playwright.yml

@@ -1,9 +1,9 @@
 name: Playwright E2E
 
+# Manual-only by design:
+# - Automatic e2e runs that gate Docker image builds live in docker-publish.yml.
+# - Keeping this workflow manual avoids running the same e2e suite twice on master pushes.
 on:
-  push:
-    branches:
-      - master
   workflow_dispatch:
 
 jobs: