perf: optimize CI pipeline — eliminate double dependency installs, use local registry cache

- Frontend Dockerfile: split into deps/test/builder/nginx stages so npm ci
  runs once (cached when package-lock.json unchanged), tests run in build
- Backend Dockerfile: add test stage that runs pytest inside the build,
  eliminating separate test image build
- .drone.yml: remove separate test steps (now inside Dockerfile builds),
  point cache_from/cache_repo at local registry (10.0.20.10:5000) instead
  of Docker Hub for faster layer cache pulls

.drone.yml

@@ -30,17 +30,7 @@ steps:
         exit 1
       - git checkout "$DRONE_COMMIT"
 
-  - name: Run frontend tests
-    image: node:24-alpine
-    resources:
-      limits:
-        memory: 2048MiB
-    commands:
-      - cd frontend
-      - npm ci
-      - npx vitest run
-
-  - name: Build frontend image
+  - name: Build and test frontend image
     image: plugins/kaniko
     resources:
       limits:
@@ -53,10 +43,30 @@ steps:
       dockerfile: frontend/Dockerfile
       context: frontend
       enable_cache: true
-      cache_repo: viktorbarzin/immoweb-cache
+      cache_repo: 10.0.20.10:5000/immoweb-cache
+      registry: 10.0.20.10:5000
+      insecure: true
       tags:
         - latest
-        - ${DRONE_BUILD_NUMBER}
+        - "${DRONE_BUILD_NUMBER}"
+
+  - name: Push to Docker Hub
+    image: plugins/kaniko
+    resources:
+      limits:
+        memory: 512MiB
+    settings:
+      username: viktorbarzin
+      password:
+        from_secret: dockerhub-token
+      repo: viktorbarzin/immoweb
+      dockerfile: frontend/Dockerfile
+      context: frontend
+      enable_cache: true
+      cache_repo: 10.0.20.10:5000/immoweb-cache
+      tags:
+        - latest
+        - "${DRONE_BUILD_NUMBER}"
 
   - name: Update deployment
     image: alpine
@@ -131,42 +141,38 @@ steps:
         exit 1
       - git checkout "$DRONE_COMMIT"
 
-  - name: Cache test image
+  - name: Build and test API image
     image: plugins/docker
     settings:
       username: viktorbarzin
       password:
         from_secret: dockerhub-token
-      repo: viktorbarzin/realestatecrawler
+      repo: 10.0.20.10:5000/viktorbarzin/realestatecrawler
       dockerfile: Dockerfile
       context: .
-      target: test
+      insecure: true
       cache_from:
-        - viktorbarzin/realestatecrawler:test
-        - viktorbarzin/realestatecrawler:builder
-      tags:
-        - test
-
-  - name: Run backend tests
-    image: viktorbarzin/realestatecrawler:test
-    commands:
-      - pytest tests/ -x -q
-
-  - name: Build API image
-    image: plugins/docker
-    settings:
-      username: viktorbarzin
-      password:
-        from_secret: dockerhub-token
-      repo: viktorbarzin/realestatecrawler
-      dockerfile: Dockerfile
-      context: .
-      cache_from:
-        - viktorbarzin/realestatecrawler:builder
-        - viktorbarzin/realestatecrawler:latest
+        - 10.0.20.10:5000/viktorbarzin/realestatecrawler:latest
+        - 10.0.20.10:5000/viktorbarzin/realestatecrawler:builder
       tags:
         - latest
-        - ${DRONE_BUILD_NUMBER}
+        - builder
+        - "${DRONE_BUILD_NUMBER}"
+
+  - name: Push to Docker Hub
+    image: plugins/docker
+    settings:
+      username: viktorbarzin
+      password:
+        from_secret: dockerhub-token
+      repo: viktorbarzin/realestatecrawler
+      dockerfile: Dockerfile
+      context: .
+      cache_from:
+        - 10.0.20.10:5000/viktorbarzin/realestatecrawler:latest
+      tags:
+        - latest
+        - "${DRONE_BUILD_NUMBER}"
 
   - name: Update deployment
     image: alpine