Build CI scripts into test-runner image instead of volume mount

DinD volume mounts don't work — the Docker daemon can't see the CI
runner's workspace volume. Instead, COPY ci/ into the Playwright
image at build time via dockerfile_inline. No volume detection needed.

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

.gitea/workflows/ci.yaml

@@ -384,32 +384,12 @@ jobs:
       - name: Checkout
         uses: actions/checkout@v4
 
-      # In DinD (Gitea runners), the workspace is a Docker volume, not a
-      # host path.  Resolve the volume backing $PWD so the test-runner
-      # container can mount the same checkout.
-      - name: Resolve workspace volume
-        id: ws
-        run: |
-          # The CI runner's own container has the workspace mounted.
-          # Find which Docker volume backs the current working directory.
-          SELF=$(cat /proc/1/cpuset 2>/dev/null | sed 's|.*/||' || hostname)
-          VOL=$(docker inspect "$SELF" 2>/dev/null \
-            | grep -oP '"Source":\s*"\K[^"]+' \
-            | head -1) || true
-          if [ -z "$VOL" ]; then
-            # Fallback: current directory (works for non-DinD environments)
-            VOL="."
-          fi
-          echo "CI_WORKSPACE_VOLUME=${VOL}" >> "$GITHUB_OUTPUT"
-          echo "Workspace volume → ${VOL}"
-
       - name: Run surface tests (compose)
         env:
           BUNDLED_PACKAGES: '*'
           ARMATURE_ADMIN_USERNAME: admin
           ARMATURE_ADMIN_PASSWORD: admin
           ARMATURE_ADMIN_EMAIL: admin@test.local
-          CI_WORKSPACE_VOLUME: ${{ steps.ws.outputs.CI_WORKSPACE_VOLUME }}
         run: |
           docker compose -f docker-compose.yml -f docker-compose.ci.yml up --build \
             --abort-on-container-exit \