Add functionality to manage and track customer credit notes

Introduces the "Avoirs" feature, including database schema, API endpoints for CRUD operations, and frontend components for viewing and managing credit notes.

Replit-Commit-Author: Agent
Replit-Commit-Session-Id: 9fcf4b21-eb0c-4e53-a567-e2ce4a6ad869
Replit-Commit-Checkpoint-Type: full_checkpoint
Replit-Commit-Screenshot-Url: https://storage.googleapis.com/screenshot-production-us-central1/1957c339-2757-4d1f-8e92-e9f71a1ce58e/9fcf4b21-eb0c-4e53-a567-e2ce4a6ad869/0C3uBiZ

client/src/components/RouterProduction.tsx

@@ -21,6 +21,7 @@ import BackupManager from "@/pages/BackupManager";
 import Utilities from "@/pages/Utilities";
 import Tasks from "@/pages/Tasks";
 import SavTickets from "@/pages/SavTickets";
+import Avoirs from "@/pages/Avoirs";
 import WeatherSettings from "@/pages/WeatherSettings";
 import Layout from "@/components/Layout";
 
@@ -96,6 +97,7 @@ function RouterProduction() {
         <Route path="/utilities" component={Utilities} />
         <Route path="/tasks" component={Tasks} />
         <Route path="/sav" component={SavTickets} />
+        <Route path="/avoirs" component={Avoirs} />
         
         {/* Routes de compatibilité - redirection vers utilities */}
         <Route path="/backup" component={Utilities} />

client/src/components/Sidebar.tsx

@@ -32,7 +32,8 @@ import {
   Settings,
   Wrench,
   FileUp,
-  Send
+  Send,
+  Receipt
 } from "lucide-react";
 
 export default function Sidebar() {
@@ -284,6 +285,12 @@ export default function Sidebar() {
       icon: Wrench, 
       roles: ["admin", "directeur", "manager", "employee"] 
     },
+    { 
+      path: "/avoirs", 
+      label: "Avoirs", 
+      icon: Receipt, 
+      roles: ["admin", "directeur", "manager"] 
+    },
   ];
 
   const adminItems = [