Add profit analytics chart and service

Introduces a new ProfitAnalyticsChart component to display profit-related metrics, including total revenue, cost, profit, and top profitable products. Updates the AnalyticsDashboard to include a Profit tab and adds a profit-analytics-service for fetching profit data from the backend.

components/analytics/AnalyticsDashboard.tsx

@@ -17,7 +17,8 @@ import {
   Activity,
   RefreshCw,
   Eye,
-  EyeOff
+  EyeOff,
+  Calculator
 } from "lucide-react";
 import { useToast } from "@/hooks/use-toast";
 import MetricsCard from "./MetricsCard";
@@ -44,6 +45,10 @@ const OrderAnalyticsChart = dynamic(() => import('./OrderAnalyticsChart'), {
   loading: () => <ChartSkeleton />
 });
 
+const ProfitAnalyticsChart = dynamic(() => import('./ProfitAnalyticsChart'), {
+  loading: () => <ChartSkeleton />
+});
+
 // Chart loading skeleton
 function ChartSkeleton() {
   return (
@@ -249,7 +254,7 @@ export default function AnalyticsDashboard({ initialData }: AnalyticsDashboardPr
         <div>
           <h3 className="text-lg font-semibold">Time Period</h3>
           <p className="text-sm text-muted-foreground">
-            Revenue and Orders tabs use time filtering. Products and Customers show all-time data.
+            Revenue, Profit, and Orders tabs use time filtering. Products and Customers show all-time data.
           </p>
         </div>
         <Select value={timeRange} onValueChange={setTimeRange}>
@@ -267,11 +272,15 @@ export default function AnalyticsDashboard({ initialData }: AnalyticsDashboardPr
       {/* Analytics Tabs */}
       <div className="space-y-6">
         <Tabs defaultValue="revenue" className="space-y-6">
-          <TabsList className="grid w-full grid-cols-4">
+          <TabsList className="grid w-full grid-cols-5">
             <TabsTrigger value="revenue" className="flex items-center gap-2">
               <TrendingUp className="h-4 w-4" />
               Revenue
             </TabsTrigger>
+            <TabsTrigger value="profit" className="flex items-center gap-2">
+              <Calculator className="h-4 w-4" />
+              Profit
+            </TabsTrigger>
             <TabsTrigger value="products" className="flex items-center gap-2">
               <Package className="h-4 w-4" />
               Products
@@ -292,6 +301,12 @@ export default function AnalyticsDashboard({ initialData }: AnalyticsDashboardPr
             </Suspense>
           </TabsContent>
 
+          <TabsContent value="profit" className="space-y-6">
+            <Suspense fallback={<ChartSkeleton />}>
+              <ProfitAnalyticsChart timeRange={timeRange} hideNumbers={hideNumbers} />
+            </Suspense>
+          </TabsContent>
+
           <TabsContent value="products" className="space-y-6">
             <Suspense fallback={<ChartSkeleton />}>
               <ProductPerformanceChart />