Phase 3: Optimize & clean up — unified projects, account enhancements, new tenant fix

- Unify reserve_components + capital_projects into single projects model with
  full CRUD backend and new Projects page frontend
- Rewrite Capital Planning to read from unified projects/planning endpoint;
  add empty state directing users to Projects page when no planning items exist
- Add default designation to assessment groups with auto-set on first creation;
  units now require an assessment group (pre-populated with default)
- Add primary account designation (one per fund type) and balance adjustment
  via journal entries against equity offset accounts (3000/3100)
- Add computed investment fields (interest earned, maturity value, days remaining)
  with PostgreSQL date arithmetic fix for DATE - DATE integer result
- Restructure sidebar: investments in Accounts tab, Year-End under Reports,
  Planning section with Projects and Capital Planning
- Fix new tenant creation seeding unwanted default chart of accounts —
  new tenants now start with a blank slate

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

frontend/src/App.tsx

@@ -12,7 +12,7 @@ import { UnitsPage } from './pages/units/UnitsPage';
 import { InvoicesPage } from './pages/invoices/InvoicesPage';
 import { PaymentsPage } from './pages/payments/PaymentsPage';
 import { VendorsPage } from './pages/vendors/VendorsPage';
-import { ReservesPage } from './pages/reserves/ReservesPage';
+import { ProjectsPage } from './pages/projects/ProjectsPage';
 import { InvestmentsPage } from './pages/investments/InvestmentsPage';
 import { CapitalProjectsPage } from './pages/capital-projects/CapitalProjectsPage';
 import { BalanceSheetPage } from './pages/reports/BalanceSheetPage';
@@ -110,7 +110,7 @@ export function App() {
         <Route path="invoices" element={<InvoicesPage />} />
         <Route path="payments" element={<PaymentsPage />} />
         <Route path="vendors" element={<VendorsPage />} />
-        <Route path="reserves" element={<ReservesPage />} />
+        <Route path="projects" element={<ProjectsPage />} />
         <Route path="investments" element={<InvestmentsPage />} />
         <Route path="capital-projects" element={<CapitalProjectsPage />} />
         <Route path="assessment-groups" element={<AssessmentGroupsPage />} />
@@ -120,7 +120,7 @@ export function App() {
         <Route path="reports/cash-flow" element={<CashFlowPage />} />
         <Route path="reports/aging" element={<AgingReportPage />} />
         <Route path="reports/sankey" element={<SankeyPage />} />
-        <Route path="year-end" element={<YearEndPage />} />
+        <Route path="reports/year-end" element={<YearEndPage />} />
         <Route path="settings" element={<SettingsPage />} />
       </Route>
     </Routes>