feat(react-router): Add React Router Instrumentation API support

[onurtemizkan]

SDK PR: getsentry/sentry-javascript#18580

Adds wizard support for React Router's https://reactrouter.com/how-to/instrumentation
(unstable_instrumentations), available in React Router 7.9.5+.

When tracing is enabled, the wizard now asks if the user wants to use the Instrumentation API.

• Configures entry.client.tsx with Sentry.reactRouterTracingIntegration({ useInstrumentationAPI: true }) and the unstable_instrumentations prop on <HydratedRouter>
• Configures entry.server.tsx with a standalone unstable_instrumentations export using Sentry.createSentryServerInstrumentation()
• Adds @sentry/react-router to Vite's optimizeDeps.exclude to prevent Vite returns 504 Outdated Optimize Dep for non-existing resource vitejs/vite#13506 in dev mode

Also fixes to the original React Router wizard:

• async async duplication when wrapping an already-async handleRequest in entry.server.tsx
• Missing NODE_ENV=production in the start script when --import instrumentation is used
• E2E test runner (run.sh) substring-matching react-router against react-router-instrumentation-api.test.ts