Initial commit: HOA Financial Intelligence Platform MVP

Multi-tenant financial management platform for homeowner associations featuring:
- NestJS backend with 16 modules (auth, accounts, transactions, budgets, units,
  invoices, payments, vendors, reserves, investments, capital projects, reports)
- React + Mantine frontend with dashboard, CRUD pages, and financial reports
- Schema-per-tenant PostgreSQL isolation with JWT-based tenant resolution
- Docker Compose infrastructure (nginx, backend, frontend, postgres, redis)
- Comprehensive seed data for Sunrise Valley HOA demo
- 39 API endpoints with Swagger documentation
- Double-entry bookkeeping with journal entries
- Budget vs actual reporting and Sankey cash flow visualization

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

frontend/src/pages/PlaceholderPage.tsx

@@ -0,0 +1,13 @@
+import { Title, Text, Card, Stack } from '@mantine/core';
+
+export function PlaceholderPage({ title }: { title: string }) {
+  return (
+    <Stack>
+      <Title order={2}>{title}</Title>
+      <Card withBorder p="xl" ta="center">
+        <Text size="lg" c="dimmed">Coming soon</Text>
+        <Text size="sm" c="dimmed" mt="sm">This feature is under development.</Text>
+      </Card>
+    </Stack>
+  );
+}