fix(web): restore shadcn theme tokens in index.css; tidy deps + eslint rule

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

web/package.json

@@ -21,7 +21,6 @@
     "lucide-react": "^1.17.0",
     "react": "^19.1.0",
     "react-dom": "^19.1.0",
-    "shadcn": "^4.10.0",
     "tailwind-merge": "^3.6.0",
     "tw-animate-css": "^1.4.0"
   },
@@ -35,6 +34,7 @@
     "@types/react": "^19.1.5",
     "@types/react-dom": "^19.1.3",
     "@vitejs/plugin-react": "^4.5.2",
+    "shadcn": "^4.10.0",
     "eslint": "^10.4.1",
     "eslint-plugin-react-hooks": "^7.1.1",
     "eslint-plugin-react-refresh": "^0.5.2",