feat(frontend): integrate @sentry/sveltekit for browser and SSR error reporting

Adds @sentry/sveltekit to hooks.client.ts and hooks.server.ts.
When VITE_SENTRY_DSN is unset (default), Sentry is fully disabled.
When set to a GlitchTip JavaScript project DSN, browser exceptions
and SSR handleError events are forwarded automatically.

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

frontend/package.json

@@ -23,6 +23,7 @@
 		"generate:api": "openapi-typescript http://localhost:8080/v3/api-docs -o ./src/lib/generated/api.ts"
 	},
 	"dependencies": {
+		"@sentry/sveltekit": "^10.53.1",
 		"@tiptap/core": "3.22.5",
 		"@tiptap/extension-mention": "3.22.5",
 		"@tiptap/starter-kit": "3.22.5",

frontend/src/hooks.client.ts

@@ -0,0 +1,10 @@
+import * as Sentry from '@sentry/sveltekit';
+
+Sentry.init({
+	dsn: import.meta.env.VITE_SENTRY_DSN,
+	environment: import.meta.env.MODE,
+	tracesSampleRate: 1.0,
+	enabled: !!import.meta.env.VITE_SENTRY_DSN
+});
+
+export const handleError = Sentry.handleErrorWithSentry();

frontend/src/hooks.server.ts

@@ -1,3 +1,4 @@
+import * as Sentry from '@sentry/sveltekit';
 import { redirect, type Handle, type HandleFetch } from '@sveltejs/kit';
 import { paraglideMiddleware } from '$lib/paraglide/server';
 import { sequence } from '@sveltejs/kit/hooks';
@@ -5,6 +6,13 @@ import { env } from 'process';
 import { cookieName, cookieMaxAge } from '$lib/paraglide/runtime';
 import { detectLocale } from '$lib/shared/server/locale';
 
+Sentry.init({
+	dsn: import.meta.env.VITE_SENTRY_DSN,
+	environment: import.meta.env.MODE,
+	tracesSampleRate: 1.0,
+	enabled: !!import.meta.env.VITE_SENTRY_DSN
+});
+
 const PUBLIC_PATHS = [
 	'/login',
 	'/logout',
@@ -113,3 +121,5 @@ export const handleFetch: HandleFetch = async ({ event, request, fetch }) => {
 };
 
 export const handle = sequence(userGroup, handleAuth, handleLocaleDetection, handleParaglide);
+
+export const handleError = Sentry.handleErrorWithSentry();