Implement Owner Panel features and maintenance mode handling

- Introduced the Owner Panel with new routes and UI components for managing guilds, user blacklists, feature flags, and bot presence.
- Added maintenance mode functionality to prevent non-owner users from executing commands during maintenance periods.
- Enhanced localization with new keys for Owner Panel features in both English and German.
- Updated job processing to include a presence refresh job, ensuring the bot's status is regularly updated.
- Improved environment configuration to support owner user IDs for access control.

apps/webui/src/app/api/owner/audit/route.ts

@@ -0,0 +1,17 @@
+import { NextResponse } from 'next/server';
+import { toApiErrorResponse } from '@/lib/auth';
+import { listOwnerAudit } from '@/lib/owner-audit';
+import { requireOwner } from '@/lib/owner-auth';
+
+export async function GET(request: Request) {
+  try {
+    await requireOwner('VIEWER');
+    const { searchParams } = new URL(request.url);
+    const limit = Math.min(Number(searchParams.get('limit') ?? 50), 100);
+    const offset = Math.max(Number(searchParams.get('offset') ?? 0), 0);
+    const entries = await listOwnerAudit(limit, offset);
+    return NextResponse.json({ entries });
+  } catch (error) {
+    return toApiErrorResponse(error);
+  }
+}