ci: bump playwright container to v1.61.1-noble (match dep bump)

The test job runs in the Playwright Docker image, whose browser builds
must match the installed playwright version.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_019t8kP8vp58ZrvaD2FqJU6A

Author: obiot

.github/workflows/main.yml

@@ -46,7 +46,8 @@ jobs:
     needs: lint
     runs-on: ubuntu-latest
     container:
-      image: mcr.microsoft.com/playwright:v1.59.1-noble
+      # must match the workspace's playwright version (root devDependencies)
+      image: mcr.microsoft.com/playwright:v1.61.1-noble
     steps:
       - uses: actions/checkout@v5
       - name: Setup node