feat: AI face enhancement with GFPGAN and CodeFormer (#61)

* feat(shared): add enhance-faces tool definition and i18n strings

* feat(ai): add face enhancement script with GFPGAN and CodeFormer support

Detects faces via MediaPipe dual-model approach, then enhances using
GFPGAN (proven) or CodeFormer (via codeformer-pip) with auto fallback.
Supports strength-based alpha blending with original image.

* feat(ai): add TypeScript bridge for face enhancement

* feat(api): add enhance-faces route with GFPGAN/CodeFormer support

* feat(web): add enhance-faces settings component and register in tool registry

* feat(docker): add CodeFormer dependency and model download

- Add codeformer-pip to both CPU and GPU requirements
- Download CodeFormer model (~375MB) at Docker build time
- Add CodeFormer to smoke test verification

* fix(enhance-faces): address code review findings

- Skip alpha blend for CodeFormer (strength already applied via fidelity weight)
- Hide "only enhance main face" checkbox when Best (CodeFormer) is selected
- Fix sensitivity slider labels (swap More/Fewer faces to match actual behavior)
- Register EnhanceFacesControls in pipeline step settings
- Remove model names from user-facing descriptions

* fix(enhance-faces): fix CodeFormer integration and Docker setup

- Add codeformer-pip install to Dockerfile with --no-deps to avoid numpy 2.x conflict
- Re-pin numpy==1.26.4 after codeformer-pip install
- Pin codeformer-pip==0.0.4 in requirements files
- Broaden auto-mode fallback to catch any Exception from CodeFormer

---------

Co-authored-by: stirling-image <stirling-image@users.noreply.github.com>

packages/shared/src/constants.ts

@@ -177,6 +177,14 @@ export const TOOLS: Tool[] = [
     icon: "Sparkles",
     route: "/image-enhancement",
   },
+  {
+    id: "enhance-faces",
+    name: "Face Enhancement",
+    description: "Restore and enhance faces with AI",
+    category: "ai",
+    icon: "ScanFace",
+    route: "/enhance-faces",
+  },
   {
     id: "colorize",
     name: "AI Colorization",
@@ -421,6 +429,7 @@ export const PYTHON_SIDECAR_TOOLS = [
   "erase-object",
   "ocr",
   "colorize",
+  "enhance-faces",
   "noise-removal",
   "red-eye-removal",
 ] as const;