Add oven batch cost to AI Quick Quote (1 batch, DefaultOvenCycleMinutes or 50 min)

Previously the quick quote omitted the oven charge entirely, so saved quotes
were under-priced relative to full quotes from the same items.

Pricing: CalculatePricing now calculates ovenBatchCost = (cycleMin/60) × OvenOperatingCostPerHour
using DefaultOvenCycleMinutes (fallback 50 min), then adds it to the total as a quote-level
charge matching how PricingCalculationService handles oven costs.

Save path: SaveQuickQuoteRequest gains OvenBatchCost + OvenCycleMinutes; the Quote record
now stores OvenBatchCost, OvenCycleMinutes, and Total = ItemsSubtotal + OvenBatchCost.

Display: results card shows a sub-line under the estimate price:
"incl. oven 1 batch 50 min: $12.00"

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/PowderCoating.Web/Controllers/AiQuickQuoteController.cs

@@ -107,6 +107,9 @@ public class AiQuickQuoteController : Controller
         var quoteNumber = await GenerateQuoteNumberAsync(companyId);
         var now = DateTime.UtcNow;
 
+        var itemsSubtotal = request.EstimatedUnitPrice * request.Quantity;
+        var ovenCycleMinutes = request.OvenCycleMinutes > 0 ? request.OvenCycleMinutes : 50;
+
         var quote = new Quote
         {
             CompanyId        = companyId,
@@ -121,12 +124,14 @@ public class AiQuickQuoteController : Controller
             CustomerPO       = request.Reference,
             MaterialCosts    = request.MaterialCost,
             LaborCosts       = request.LaborCost,
-            ItemsSubtotal    = request.EstimatedUnitPrice * request.Quantity,
-            SubTotal         = request.EstimatedUnitPrice * request.Quantity,
-            Total            = request.EstimatedUnitPrice * request.Quantity,
+            ItemsSubtotal    = itemsSubtotal,
+            OvenBatches      = 1,
+            OvenCycleMinutes = ovenCycleMinutes,
+            OvenBatchCost    = request.OvenBatchCost,
+            SubTotal         = itemsSubtotal,
+            Total            = itemsSubtotal + request.OvenBatchCost,
             TaxPercent       = 0,
-            TaxAmount        = 0,
-            OvenBatches      = 1
+            TaxAmount        = 0
         };
 
         if (draftStatus != null)