Fix test-runner volume mount for DinD workspace

In Gitea runner pods, the repo checkout lives in a Docker volume, not
a host path. The `.:/work` mount in docker-compose.ci.yml resolved to
the Docker daemon's CWD (empty), causing "No such file or directory".

Resolve the actual Docker volume backing the CI workspace at runtime
and pass it via CI_WORKSPACE_VOLUME env var. Falls back to `.` for
local (non-DinD) usage.

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

.gitea/workflows/ci.yaml

@@ -384,12 +384,32 @@ 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 \

docker-compose.ci.yml

@@ -31,7 +31,7 @@ services:
         condition: service_healthy
     working_dir: /work
     volumes:
-      - .:/work
+      - ${CI_WORKSPACE_VOLUME:-.}:/work
     environment:
       SERVER_URL: http://armature:80
       ADMIN_USER: admin