fix(ci): Add git safe.directory to Playwright Docker image

The container runs as root but the GitHub Actions workspace is owned by
a different user, causing "dubious ownership" errors when rollup (or
other tools) shell out to git. Baking `safe.directory '*'` into the
image fixes this for all container jobs.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: mydea

.github/docker/playwright.Dockerfile

@@ -5,3 +5,8 @@ FROM mcr.microsoft.com/playwright:v${PLAYWRIGHT_VERSION}-noble
 
 # Install yarn (v1) for the monorepo
 RUN npm install -g yarn@1.22.22
+
+# Mark GitHub Actions workspace as safe for git.
+# The container runs as root but the workspace is owned by a different user,
+# causing "dubious ownership" errors in git operations (e.g. rollup build).
+RUN git config --global --add safe.directory '*'