feat: add output filename suffixes, CPU fallback for GPU packages, and fix e2e tests

- Add tool-specific suffix to output filenames so downloads don't overwrite originals (batch & single-tool routes)
- Skip deleting shared models when uninstalling a bundle that shares models with another installed bundle
- Auto-detect NVIDIA GPU and swap GPU-only pip packages (onnxruntime-gpu, paddlepaddle-gpu) for CPU equivalents
- Refactor docker-compose with YAML anchors and explicit cpu/gpu profiles
- Add libheif-plugin-x265 to Dockerfile
- Fix install-all queue logic to handle concurrent individual installs and clear stale errors
- Unify playwright docker config to use same test dir with API_URL env var
- Fix flaky e2e selectors, rename Strip Metadata → Remove Metadata, handle collage custom dropzone, improve fallback test image generation

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

docker/docker-compose.yml

@@ -1,37 +1,47 @@
 name: ashim
 
+# Usage:
+#   CPU:   docker compose --profile cpu up -d
+#   GPU:   docker compose --profile gpu up -d
+
+x-common: &common
+  build:
+    context: ..
+    dockerfile: docker/Dockerfile
+  image: ashim:latest
+  ports:
+    - "1349:1349"
+  volumes:
+    - ashim-data:/data
+    - ashim-workspace:/tmp/workspace
+  environment:
+    - AUTH_ENABLED=true
+    - DEFAULT_USERNAME=admin
+    - DEFAULT_PASSWORD=admin
+    - SKIP_MUST_CHANGE_PASSWORD=${SKIP_MUST_CHANGE_PASSWORD:-false}
+    - RATE_LIMIT_PER_MIN=${RATE_LIMIT_PER_MIN:-100}
+  restart: unless-stopped
+  healthcheck:
+    test: ["CMD", "curl", "-f", "http://localhost:1349/api/v1/health"]
+    interval: 30s
+    timeout: 5s
+    start_period: 60s
+    retries: 3
+  logging:
+    driver: json-file
+    options:
+      max-size: "10m"
+      max-file: "3"
+
 services:
   ashim:
-    build:
-      context: ..
-      dockerfile: docker/Dockerfile
-    image: ashim:latest
+    <<: *common
     container_name: ashim
-    ports:
-      - "1349:1349"
-    volumes:
-      - ashim-data:/data
-      - ashim-workspace:/tmp/workspace
-    environment:
-      - AUTH_ENABLED=true
-      - DEFAULT_USERNAME=admin
-      - DEFAULT_PASSWORD=admin
-    restart: unless-stopped
-    healthcheck:
-      test: ["CMD", "curl", "-f", "http://localhost:1349/api/v1/health"]
-      interval: 30s
-      timeout: 5s
-      start_period: 60s
-      retries: 3
-    logging:
-      driver: json-file
-      options:
-        max-size: "10m"
-        max-file: "3"
+    profiles:
+      - cpu
 
   ashim-gpu:
-    extends:
-      service: ashim
+    <<: *common
     container_name: ashim-gpu
     profiles:
       - gpu