chore(deps): clear Dependabot alerts — React 19, react-router 8, Vite 7

Bumps both frontend apps (site, admin-ui):
- vite 5.4 -> 7.3.6 (pulls esbuild 0.28, patched dev-server CVEs)
- @vitejs/plugin-react 4 -> 5 (babel 7.29.7)
- postcss 8.4 -> 8.5.25
- react-router-dom 6.27 -> react-router 8.3.0 (package renamed
  upstream in v8; imports swapped in src). Fixes the open-redirect
  advisories with no patched 6.x, plus the RSC CSRF advisory
  (GHSA-qwww-vcr4-c8h2) that only 8.3.0 patches.
- react/react-dom 18.3 -> 19.2 (required by react-router 8)

npm audit: 0 vulnerabilities in both apps. tsc + vite build clean.

DorkNet.Server/admin-ui/package.json

@@ -11,19 +11,19 @@
   },
   "dependencies": {
     "@zip.js/zip.js": "^2.7.52",
-    "react": "^18.3.1",
-    "react-dom": "^18.3.1",
-    "react-router-dom": "^6.27.0"
+    "react": "^19.2.8",
+    "react-dom": "^19.2.8",
+    "react-router": "^8.3.0"
   },
   "devDependencies": {
     "@types/node": "^22.9.1",
-    "@types/react": "^18.3.12",
-    "@types/react-dom": "^18.3.1",
-    "@vitejs/plugin-react": "^4.3.3",
+    "@types/react": "^19.2.18",
+    "@types/react-dom": "^19.2.4",
+    "@vitejs/plugin-react": "^5.2.0",
     "autoprefixer": "^10.4.20",
-    "postcss": "^8.4.49",
+    "postcss": "^8.5.25",
     "tailwindcss": "^3.4.15",
     "typescript": "^5.6.3",
-    "vite": "^5.4.11"
+    "vite": "^7.3.6"
   }
 }