refactor: fix architecture violations with provider patterns and dependency inversion

Major changes:
- Add AuditProvider protocol for cross-module audit logging
- Move customer order operations to orders module (dependency inversion)
- Add customer order metrics via MetricsProvider pattern
- Fix missing db parameter in get_admin_context() calls
- Move ProductMedia relationship to catalog module (proper ownership)
- Add marketplace breakdown stats to marketplace_widgets

New files:
- contracts/audit.py - AuditProviderProtocol
- core/services/audit_aggregator.py - Aggregates audit providers
- monitoring/services/audit_provider.py - Monitoring audit implementation
- orders/services/customer_order_service.py - Customer order operations
- orders/routes/api/vendor_customer_orders.py - Customer order endpoints
- catalog/services/product_media_service.py - Product media service
- Architecture documentation for patterns

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

app/modules/marketplace/services/marketplace_widgets.py

@@ -14,9 +14,11 @@ import logging
 from sqlalchemy.orm import Session
 
 from app.modules.contracts.widgets import (
+    BreakdownWidget,
     DashboardWidget,
     DashboardWidgetProviderProtocol,
     ListWidget,
+    WidgetBreakdownItem,
     WidgetContext,
     WidgetListItem,
 )
@@ -187,7 +189,7 @@ class MarketplaceWidgetProvider:
             .count()
         )
 
-        return [
+        widgets = [
             DashboardWidget(
                 key="marketplace.recent_imports",
                 widget_type="list",
@@ -204,6 +206,82 @@ class MarketplaceWidgetProvider:
             )
         ]
 
+        # Add marketplace breakdown widget
+        breakdown_widget = self._get_marketplace_breakdown_widget(db)
+        if breakdown_widget:
+            widgets.append(breakdown_widget)
+
+        return widgets
+
+    def _get_marketplace_breakdown_widget(
+        self,
+        db: Session,
+    ) -> DashboardWidget | None:
+        """
+        Get a breakdown widget showing statistics per marketplace.
+
+        Returns:
+            DashboardWidget with BreakdownWidget data, or None if no data
+        """
+        from sqlalchemy import func
+
+        from app.modules.marketplace.models import MarketplaceProduct
+
+        try:
+            marketplace_stats = (
+                db.query(
+                    MarketplaceProduct.marketplace,
+                    func.count(MarketplaceProduct.id).label("total_products"),
+                    func.count(func.distinct(MarketplaceProduct.vendor_name)).label(
+                        "unique_vendors"
+                    ),
+                    func.count(func.distinct(MarketplaceProduct.brand)).label(
+                        "unique_brands"
+                    ),
+                )
+                .filter(MarketplaceProduct.marketplace.isnot(None))
+                .group_by(MarketplaceProduct.marketplace)
+                .all()
+            )
+
+            if not marketplace_stats:
+                return None
+
+            total_products = sum(stat.total_products for stat in marketplace_stats)
+
+            breakdown_items = [
+                WidgetBreakdownItem(
+                    label=stat.marketplace or "Unknown",
+                    value=stat.total_products,
+                    secondary_value=stat.unique_vendors,
+                    percentage=(
+                        round(stat.total_products / total_products * 100, 1)
+                        if total_products > 0
+                        else 0
+                    ),
+                    icon="globe",
+                )
+                for stat in marketplace_stats
+            ]
+
+            return DashboardWidget(
+                key="marketplace.breakdown",
+                widget_type="breakdown",
+                title="Products by Marketplace",
+                category="marketplace",
+                data=BreakdownWidget(
+                    items=breakdown_items,
+                    total=total_products,
+                ),
+                icon="chart-pie",
+                description="Product distribution across marketplaces",
+                order=30,
+            )
+
+        except Exception as e:
+            logger.warning(f"Failed to get marketplace breakdown widget: {e}")
+            return None
+
 
 # Singleton instance
 marketplace_widget_provider = MarketplaceWidgetProvider()