chore: upgrade Vite to 8.0.14 and plugin-react to 6.0.2

- vite 6.4.2 to 8.0.14
- @vitejs/plugin-react 5.2.0 to 6.0.2
- Migrate optimizeDeps.esbuildOptions to rolldownOptions (Vite 8 uses rolldown)
- Remove @esbuild-plugins/node-globals-polyfill (no longer needed)

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

vite.config.js

@@ -4,7 +4,6 @@ import { sentryVitePlugin } from '@sentry/vite-plugin';
 import { wasm } from '@rollup/plugin-wasm';
 import { viteStaticCopy } from 'vite-plugin-static-copy';
 import { vanillaExtractPlugin } from '@vanilla-extract/vite-plugin';
-import { NodeGlobalsPolyfillPlugin } from '@esbuild-plugins/node-globals-polyfill';
 import inject from '@rollup/plugin-inject';
 import { VitePWA } from 'vite-plugin-pwa';
 import fs from 'fs';
@@ -127,16 +126,10 @@ export default defineConfig({
     }),
   ],
   optimizeDeps: {
-    esbuildOptions: {
+    rolldownOptions: {
       define: {
         global: 'globalThis',
       },
-      plugins: [
-        NodeGlobalsPolyfillPlugin({
-          process: false,
-          buffer: true,
-        }),
-      ],
     },
   },
   build: {