feat: Complete GlitchTip error monitoring integration

- Add sentry.client.config.ts, sentry.server.config.ts, sentry.edge.config.ts
- Create /api/glitchtip-tunnel route for bypassing ad blockers
- Add SentryInit component for client-side initialization
- Add instrumentation.ts for server/edge initialization
- Integrate Sentry.captureException in error handlers
- Remove test button after verifying integration works

Env vars: NEXT_PUBLIC_GLITCHTIP_DSN, GLITCHTIP_DSN

src/components/SentryInit.tsx

@@ -0,0 +1,48 @@
+'use client';
+
+import { useEffect } from 'react';
+import * as Sentry from '@sentry/nextjs';
+
+export default function SentryInit() {
+    useEffect(() => {
+        const dsn = process.env.NEXT_PUBLIC_GLITCHTIP_DSN;
+
+        console.log('[Sentry Debug] NEXT_PUBLIC_GLITCHTIP_DSN:', dsn ? dsn.substring(0, 40) + '...' : 'NOT SET');
+
+        if (!dsn) {
+            console.warn('[Sentry] Client disabled - no DSN configured');
+            return;
+        }
+
+        try {
+            // Check if already initialized
+            const existingClient = Sentry.getClient();
+            if (existingClient) {
+                console.log('[Sentry] Already initialized, skipping');
+                return;
+            }
+
+            Sentry.init({
+                dsn,
+                environment: process.env.NODE_ENV || 'development',
+                sampleRate: 1.0,
+                tracesSampleRate: 0.1,
+                tunnel: '/api/glitchtip-tunnel',
+                debug: true,
+                beforeSend(event) {
+                    console.log('[Sentry] Sending event:', event.event_id);
+                    return event;
+                },
+            });
+
+            console.log('[Sentry] ✅ Client initialized successfully');
+
+            // Test that it works
+            console.log('[Sentry] Client:', Sentry.getClient() ? 'OK' : 'FAILED');
+        } catch (err) {
+            console.error('[Sentry] Initialization error:', err);
+        }
+    }, []);
+
+    return null;
+}