Parallelize API tests and build, gate publish on test pass

Same pattern as the frontend pipeline: build pushes to a staging
tag (build-N) in parallel with tests. Tests split into unit and
integration shards using a shared venv from the workspace. Publish
step uses skopeo to copy the manifest to final tags (:N, :latest,
:builder) only after all tests and the build succeed. Named the
final Dockerfile stage 'production' so target skips the test stage.

.drone.yml

@@ -188,8 +188,44 @@ steps:
         exit 1
       - git checkout "$DRONE_COMMIT"
 
-  - name: Build and test API image
+  - name: install-api-deps
+    image: python:3.13-slim
+    depends_on:
+      - clone
+    commands:
+      - apt-get update && apt-get install -y --no-install-recommends libglib2.0-0
+      - python -m venv .venv
+      - .venv/bin/pip install --quiet --upgrade pip
+      - >-
+        .venv/bin/pip install --quiet
+        pytest pytest-asyncio pytest-cov httpx fakeredis aioresponses
+        fastapi uvicorn sqlmodel sqlalchemy alembic pyjwt cryptography
+        celery redis click aiohttp aiohttp-socks pillow numpy pytesseract
+        opentelemetry-api opentelemetry-sdk opentelemetry-exporter-prometheus
+        opentelemetry-instrumentation-fastapi opentelemetry-instrumentation-sqlalchemy
+        python-dotenv webauthn apprise tenacity prometheus-client
+        email-validator opencv-python-headless tqdm pandas cachetools watchdog
+
+  - name: test-unit
+    image: python:3.13-slim
+    depends_on:
+      - install-api-deps
+    commands:
+      - apt-get update && apt-get install -y --no-install-recommends libglib2.0-0
+      - .venv/bin/pytest tests/unit/ -v --tb=short
+
+  - name: test-integration
+    image: python:3.13-slim
+    depends_on:
+      - install-api-deps
+    commands:
+      - apt-get update && apt-get install -y --no-install-recommends libglib2.0-0
+      - .venv/bin/pytest tests/integration/ tests/regression/ tests/e2e/ tests/test_listing_geojson.py -v --tb=short
+
+  - name: build-api-image
     image: plugins/docker
+    depends_on:
+      - clone
     environment:
       DOCKER_BUILDKIT: 1
     settings:
@@ -199,16 +235,32 @@ steps:
       repo: viktorbarzin/realestatecrawler
       dockerfile: Dockerfile
       context: .
+      target: production
       cache_from:
         - viktorbarzin/realestatecrawler:latest
         - viktorbarzin/realestatecrawler:builder
       tags:
-        - latest
-        - builder
-        - "${DRONE_BUILD_NUMBER}"
+        - "build-${DRONE_BUILD_NUMBER}"
+
+  - name: publish-api-image
+    image: alpine
+    depends_on:
+      - test-unit
+      - test-integration
+      - build-api-image
+    environment:
+      DOCKERHUB_TOKEN:
+        from_secret: dockerhub-token
+    commands:
+      - apk add --no-cache skopeo
+      - 'skopeo copy --src-creds "viktorbarzin:$DOCKERHUB_TOKEN" --dest-creds "viktorbarzin:$DOCKERHUB_TOKEN" "docker://docker.io/viktorbarzin/realestatecrawler:build-${DRONE_BUILD_NUMBER}" "docker://docker.io/viktorbarzin/realestatecrawler:${DRONE_BUILD_NUMBER}"'
+      - 'skopeo copy --src-creds "viktorbarzin:$DOCKERHUB_TOKEN" --dest-creds "viktorbarzin:$DOCKERHUB_TOKEN" "docker://docker.io/viktorbarzin/realestatecrawler:build-${DRONE_BUILD_NUMBER}" "docker://docker.io/viktorbarzin/realestatecrawler:latest"'
+      - 'skopeo copy --src-creds "viktorbarzin:$DOCKERHUB_TOKEN" --dest-creds "viktorbarzin:$DOCKERHUB_TOKEN" "docker://docker.io/viktorbarzin/realestatecrawler:build-${DRONE_BUILD_NUMBER}" "docker://docker.io/viktorbarzin/realestatecrawler:builder"'
 
   - name: Update deployment
     image: alpine
+    depends_on:
+      - publish-api-image
     commands:
       - apk add curl
       - 'curl -s -X PATCH "https://kubernetes:6443/apis/apps/v1/namespaces/realestate-crawler/deployments/realestate-crawler-api" -H "Authorization: Bearer $(cat /var/run/secrets/kubernetes.io/serviceaccount/token)" -H "Content-Type: application/json-patch+json" -k -d ''[{"op":"replace","path":"/spec/template/spec/containers/0/image","value":"viktorbarzin/realestatecrawler:''"$DRONE_BUILD_NUMBER"''"}]'' | head'
@@ -217,6 +269,8 @@ steps:
 
   - name: verify-deploy
     image: alpine
+    depends_on:
+      - Update deployment
     commands:
       - apk add --no-cache curl jq
       - |