feat: add rental income dashboard with comprehensive analytics

- Add new /api/revenus endpoints for rental income data
  - GET /summary: KPIs, monthly trends, breakdown by property, top unpaid
  - GET /details: detailed rental records with filtering
  - GET /by-lot: revenue aggregation by unit
  - GET /immeubles: properties list with revenue stats

- Add RevenusPage with full dashboard layout
  - 6 KPI cards: total revenue, payments, unpaid, collection rate, active tenants, occupied units
  - Monthly evolution chart (rent, payments, unpaid)
  - Property breakdown donut chart
  - Top unpaid tenants list
  - Detailed revenue table with pagination and CSV export

- Add filters panel (property, type, dates, unpaid only, history months)
- Display property address instead of code in all components
- Add navigation link in header (Revenus)

frontend/src/router.js

@@ -2,6 +2,7 @@ import { createRouter, createWebHistory } from 'vue-router'
 import HomePage from './pages/HomePage.vue'
 import ExtractPage from './pages/ExtractPage.vue'
 import AnalyticsPage from './pages/AnalyticsPage.vue'
+import RevenusPage from './pages/RevenusPage.vue'
 
 const routes = [
   {
@@ -18,6 +19,11 @@ const routes = [
     path: '/analytics',
     name: 'analytics',
     component: AnalyticsPage
+  },
+  {
+    path: '/revenus',
+    name: 'revenus',
+    component: RevenusPage
   }
 ]