Add comprehensive platform administration panel

- Database: Add login_history, ai_recommendation_log tables; is_platform_owner
  column on users; subscription fields on organizations (payment_date,
  confirmation_number, renewal_date)
- Backend: New AdminAnalyticsService with platform metrics, tenant detail, and
  health score calculations (0-100 based on activity, budget, transactions,
  members, AI usage)
- Backend: Login/org-switch now records to login_history; AI recommendations
  logged to ai_recommendation_log; platform owner protected from superadmin toggle
- Frontend: 4-tab admin panel (Dashboard, Organizations, Users, Tenant Health)
  with tenant detail drawer, subscription management, health scoring visualization
- Platform owner account (admin@hoaledgeriq.com) auto-redirects to admin panel
- Seed data includes platform owner account and sample login history

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

frontend/src/components/layout/Sidebar.tsx

@@ -17,6 +17,7 @@ import {
   IconChartAreaLine,
   IconClipboardCheck,
   IconSparkles,
+  IconHeartRateMonitor,
 } from '@tabler/icons-react';
 import { useAuthStore } from '../../stores/authStore';
 
@@ -87,12 +88,44 @@ export function Sidebar({ onNavigate }: SidebarProps) {
   const navigate = useNavigate();
   const location = useLocation();
   const user = useAuthStore((s) => s.user);
+  const currentOrg = useAuthStore((s) => s.currentOrg);
+  const organizations = useAuthStore((s) => s.organizations);
+  const isAdminOnly = location.pathname.startsWith('/admin') && !currentOrg;
 
   const go = (path: string) => {
     navigate(path);
     onNavigate?.();
   };
 
+  // When on admin route with no org selected, show admin-only sidebar
+  if (isAdminOnly && user?.isSuperadmin) {
+    return (
+      <ScrollArea p="sm">
+        <Text size="xs" c="dimmed" fw={700} tt="uppercase" px="sm" pb={4}>
+          Platform Administration
+        </Text>
+        <NavLink
+          label="Admin Panel"
+          leftSection={<IconCrown size={18} />}
+          active={location.pathname === '/admin'}
+          onClick={() => go('/admin')}
+          color="red"
+        />
+        {organizations && organizations.length > 0 && (
+          <>
+            <Divider my="sm" />
+            <NavLink
+              label="Switch to Tenant"
+              leftSection={<IconBuildingBank size={18} />}
+              onClick={() => go('/select-org')}
+              variant="subtle"
+            />
+          </>
+        )}
+      </ScrollArea>
+    );
+  }
+
   return (
     <ScrollArea p="sm">
       {navSections.map((section, sIdx) => (