fix(ci): use --network host for Mongo + add diagnostics

Wait-for-Mongo timed out at 30s after Start-MongoDB succeeded — typical
Docker-in-Docker symptom where -p port mapping binds to a network the
runner's node process can't see. --network host puts Mongo in the
runner's network namespace so localhost:27017 reaches it.

Also dump 'docker ps' after start and 'docker logs mongo-ci' on failure
so the next-step debugging isn't blind.

.forgejo/workflows/test.yml

@@ -39,9 +39,14 @@ jobs:
       - run: npm ci
       - run: npx playwright install --with-deps chromium
       - name: Start MongoDB
-        run: docker run -d --name mongo-ci -p 27017:27017 mongo:7
+        run: |
+          docker run -d --name mongo-ci --network host mongo:7
+          docker ps
       - name: Wait for MongoDB
         run: timeout 30 sh -c 'until nc -z localhost 27017; do sleep 1; done'
+      - name: MongoDB log on failure
+        if: failure()
+        run: docker logs mongo-ci || true
       - run: npm run build
       - name: Start server
         run: node .output/server/index.mjs > /tmp/server.log 2>&1 &
@@ -96,9 +101,14 @@ jobs:
       - run: npm ci
       - run: npx playwright install --with-deps chromium
       - name: Start MongoDB
-        run: docker run -d --name mongo-ci -p 27017:27017 mongo:7
+        run: |
+          docker run -d --name mongo-ci --network host mongo:7
+          docker ps
       - name: Wait for MongoDB
         run: timeout 30 sh -c 'until nc -z localhost 27017; do sleep 1; done'
+      - name: MongoDB log on failure
+        if: failure()
+        run: docker logs mongo-ci || true
       - run: npm run build
       - name: Start server
         run: node .output/server/index.mjs > /tmp/server.log 2>&1 &