Bump typescript from 5.33 to 6.0.3 in /web

TypeScript 6 added stricter checking (TS2882) for side-effect imports of
non-TS files (e.g. `import './App.css'`), requiring an ambient module
declaration. Added `declare module "*.css"` to src/declaration.d.ts
alongside the existing *.svg/underscore declarations.

Author: codeafix

web/package-lock.json

@@ -18,7 +18,7 @@
     "react-bootstrap-icons": "^1.4.0",
     "react-dom": "^18.2.0",
     "react-router-dom": "7.17.0",
-    "typescript": "^5.3.3",
+    "typescript": "^6.0.3",
     "underscore": "^1.13.8",
     "vite": "^6.4.2",
     "vite-tsconfig-paths": "^6.1.1"

web/package.json

@@ -1,2 +1,3 @@
 declare module "*.svg"
+declare module "*.css"
 declare module "underscore"