fix: capture React root errors in Sentry

docs/adr/0002-sentry-observability.md

@@ -18,7 +18,10 @@ Use the pinned `@sentry/react` 10.73.0 SDK. Initialize it before the application
 router is created, and wrap `createBrowserRouter` with Sentry's current React
 Router compatibility API. Configure the browser tracing integration with a 100%
 transaction sample rate, and propagate trace headers only to the SPA origin and
-the configured `VITE_API_URL` base.
+the configured `VITE_API_URL` base. Pass `Sentry.reactErrorHandler()` as the
+`onCaughtError`, `onUncaughtError`, and `onRecoverableError` callbacks of
+`ReactDOM.createRoot`, so React 19's root error hooks capture caught, uncaught,
+and recoverable component errors as Sentry events.
 
 The DSN comes from `VITE_SENTRY_DSN`. It is intentionally treated as public
 browser configuration because every `VITE_` value is embedded in the built

src/main.tsx

@@ -1,3 +1,5 @@
+import * as Sentry from "@sentry/react";
+
 import "@/observability/sentry";
 
 import React from "react";
@@ -12,7 +14,11 @@ if (!rootElement) {
   throw new Error("Root element #root not found");
 }
 
-ReactDOM.createRoot(rootElement).render(
+ReactDOM.createRoot(rootElement, {
+  onCaughtError: Sentry.reactErrorHandler(),
+  onRecoverableError: Sentry.reactErrorHandler(),
+  onUncaughtError: Sentry.reactErrorHandler(),
+}).render(
   <React.StrictMode>
     <AppProviders>
       <AppRoot />