feat(tenancies-p7): 4 module-gated dashboard widgets

- tenancy-reports.service.ts: 4 read-only query functions backing the
  widgets. Heatmap uses a months×areas SQL grid with date-range overlap;
  renewals-at-risk filters active tenancies whose end_date is inside a
  90d window with NO successor pending/active row already minted on the
  same berth; revenue forecast buckets active tenancies by their
  end-date quarter; tenure breakdown is a simple GROUP BY status='active'.
- 4 new API routes under /api/v1/dashboard/tenancy-*:
  - tenancy-occupancy (heatmap)
  - tenancy-renewals (at-risk list)
  - tenancy-revenue (forecast)
  - tenancy-tenure (breakdown)
  Each prepended with assertTenanciesModuleEnabled so a port without
  the module gets 404 instead of an empty payload.
- 4 widget components:
  - TenancyOccupancyHeatmapWidget — areas × months table with shaded
    cells (5-tier emerald ramp by occupancy %)
  - TenancyRenewalsAtRiskWidget — top-10 list, 30-day urgency badge
  - TenancyRevenueForecastWidget — horizontal bar list by quarter,
    currency-formatted totals
  - TenancyByTenureTypeWidget — proportional bars, color-coded per
    tenure type
- WidgetIntegration union extended with 'tenancies_module'; the
  useDashboardIntegrations hook reads it off PortProvider (no extra
  fetch). All four widgets register with selfGates=true +
  requires='tenancies_module' so the picker AND render path filter
  them out when the module is off.

Verified: tsc clean, 1493/1493 vitest.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/hooks/use-dashboard-integrations.ts

@@ -1,6 +1,7 @@
 'use client';
 
 import { useUmamiActive } from '@/components/website-analytics/use-website-analytics';
+import { useTenanciesModuleEnabled } from '@/providers/port-provider';
 import type { WidgetIntegration } from '@/components/dashboard/widget-registry';
 
 /**
@@ -35,11 +36,16 @@ export function useDashboardIntegrations(): {
   // a Documenso widget is added before this hook is updated.
   const documensoAvailable = true;
 
+  // Tenancies module flag is resolved server-side in the dashboard layout
+  // and surfaced through PortProvider — no extra round-trip.
+  const tenanciesModuleAvailable = useTenanciesModuleEnabled();
+
   return {
     loading: umami.isLoading,
     available: {
       umami: umamiAvailable,
       documenso: documensoAvailable,
+      tenancies_module: tenanciesModuleAvailable,
     },
   };
 }