Fix NullReferenceException on Quote Details when quote total is zero

PricingBreakdown was only populated when quote.Total > 0, but the Details
view unconditionally dereferences PricingBreakdown.ItemsSubtotal. Sandblast-
only quotes can legitimately have a $0 total (no powder/oven costs), leaving
PricingBreakdown null and crashing the Details render.

Removed the Total > 0 guard from both Details action overloads — always
populate PricingBreakdown from the stored snapshot fields (all values are 0
for an unpriced or sandblast-only quote, which is safe for display).

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

src/PowderCoating.Web/Controllers/QuotesController.cs

@@ -365,8 +365,6 @@ public class QuotesController : Controller
             }
 
             // Build pricing breakdown from stored snapshot values — never recalculate on load
-            if (quote.Total > 0)
-            {
             quoteDto.PricingBreakdown = new QuotePricingBreakdownDto
             {
                 MaterialCosts           = quote.MaterialCosts,
@@ -391,7 +389,6 @@ public class QuotesController : Controller
                 TaxAmount               = quote.TaxAmount,
                 Total                   = quote.Total
             };
-            }
 
             // Load change history
             var changeHistories = await _unitOfWork.Quotes.GetChangeHistoryAsync(id.Value);
@@ -544,8 +541,6 @@ public class QuotesController : Controller
             var currentUser = await _userManager.GetUserAsync(User);
 
             // Populate pricing breakdown from stored snapshot values — never recalculate on load
-            if (quote.Total > 0)
-            {
             quoteDto.PricingBreakdown = new QuotePricingBreakdownDto
             {
                 MaterialCosts           = quote.MaterialCosts,
@@ -570,7 +565,6 @@ public class QuotesController : Controller
                 TaxAmount               = quote.TaxAmount,
                 Total                   = quote.Total
             };
-            }
             if (currentUser?.CompanyId == null)
             {
                 TempData["Error"] = "Company information not found.";