chore: auto-sync favicon from DS via postinstall script

favicon.svg is now copied from @cameleer/design-system/assets on
npm install via postinstall hook. Removed from git tracking
(.gitignore). Updates automatically when DS version changes.

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

ui/.gitignore

@@ -1,2 +1,3 @@
 node_modules
 dist
+public/favicon.svg

ui/package.json

@@ -11,7 +11,8 @@
     "lint": "eslint .",
     "preview": "vite preview",
     "generate-api": "openapi-typescript src/api/openapi.json -o src/api/schema.d.ts",
-    "generate-api:live": "curl -s http://localhost:8081/api/v1/api-docs -o src/api/openapi.json && openapi-typescript src/api/openapi.json -o src/api/schema.d.ts"
+    "generate-api:live": "curl -s http://localhost:8081/api/v1/api-docs -o src/api/openapi.json && openapi-typescript src/api/openapi.json -o src/api/schema.d.ts",
+    "postinstall": "node -e \"require('fs').copyFileSync('node_modules/@cameleer/design-system/assets/cameleer3-logo.svg','public/favicon.svg')\""
   },
   "dependencies": {
     "@cameleer/design-system": "^0.1.37",