feat: implement Ads Performance tab

- types.ts: Add conversions field to CombinedKPIs
- dataProcessor.ts: Populate conversions in mergeSalesAndAdsData
- AdsPerformance.tsx: New component with aggregated advertising metrics and detailed product table
- App.tsx: Add Ads view to switcher and render AdsPerformance component
- Icons.tsx: Added icon support for the new Ads tab

services/dataProcessor.ts

@@ -569,6 +569,7 @@ export const mergeSalesAndAdsData = (
             cost: adCost,
             clicks: adClicks,
             impressions: adImpressions,
+            conversions: ad?.conversions || 0,
             salesOrganic,
             unitsOrganic,
             paidSalesShare: salesTotal > 0 ? (adSales / salesTotal) * 100 : 0,
@@ -606,6 +607,7 @@ export const mergeSalesAndAdsData = (
                 cost: ad.cost,
                 clicks: ad.clicks,
                 impressions: ad.impressions,
+                conversions: ad.conversions,
                 salesOrganic: 0,
                 unitsOrganic: 0,
                 paidSalesShare: 0,