Phase 5: Photo Pre-Editor (Filerobot)

- Added react-filerobot-image-editor dependency
- PhotoPreEditor component with full editing capabilities
- Crop, filters, adjustments, annotations, watermark tabs
- Opens after image upload, before adding to canvas
- Exports edited image as PNG for canvas use

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

client/package.json

@@ -15,7 +15,8 @@
     "react-konva": "^18.2.10",
     "konva": "^9.3.18",
     "use-image": "^1.1.1",
-    "@xenova/transformers": "^2.17.2"
+    "@xenova/transformers": "^2.17.2",
+    "react-filerobot-image-editor": "^4.8.1"
   },
   "devDependencies": {
     "@eslint/js": "^9.39.4",