fix: add placeholders for dashboard data to prevent 500 errors

web/src/api/system/api.ts

@@ -57,6 +57,23 @@ export interface DashboardStats {
     commit_hash: string //Git commit hash used to build this system version
 }
 
+export const INITIAL_DASHBOARD_STATS: DashboardStats = {
+    account_count: 0,
+    email_count: 0,
+    total_size_bytes: 0,
+    storage_usage_bytes: 0,
+    index_usage_bytes: 0,
+    recent_activity: [],
+    top_senders: [],
+    top_accounts: [],
+    with_attachment_count: 0,
+    without_attachment_count: 0,
+    top_largest_emails: [],
+    system_version: '0.0.0',
+    commit_hash: 'n/a'
+};
+
+
 export interface TimeBucket {
     timestamp_ms: number;   // Timestamp in milliseconds
     count: number;  // Number of emails in this time bucket

web/src/features/dashboard/index.tsx

@@ -25,7 +25,7 @@ import { XAxis, YAxis, CartesianGrid, Tooltip, ResponsiveContainer, PieChart, Pi
 import { Mail, HardDrive, Database, Users, Inbox, Info } from 'lucide-react';
 import { formatBytes, formatNumber } from '@/lib/utils';
 import { useQuery } from '@tanstack/react-query';
-import { get_dashboard_stats, TimeBucket } from '@/api/system/api';
+import { get_dashboard_stats, INITIAL_DASHBOARD_STATS, TimeBucket } from '@/api/system/api';
 import { Main } from '@/components/layout/main';
 import { FixedHeader } from '@/components/layout/fixed-header';
 import { useTranslation } from 'react-i18next';
@@ -108,6 +108,7 @@ export default function MailArchiveDashboard() {
     queryKey: ['dashboard-stats'],
     enabled: !!token,
     queryFn: get_dashboard_stats,
+    placeholderData: INITIAL_DASHBOARD_STATS,
   });
 
   const { t, i18n } = useTranslation();