Phase 2: Eliminate ApplicationDbContext from domain controllers

Migrated InvoicesController, QuotesController, JobsController, BillsController,
PurchaseOrdersController, and CustomersController to route all data access
through IUnitOfWork typed/generic repositories instead of injecting
ApplicationDbContext directly.

New typed repositories added: IJobRepository (GetScheduledJobsForDateAsync,
GetActiveJobsForMobileAsync, LoadForCostingAsync), INotificationLogRepository
(GetLatestForJobAsync, GetAllForJobAsync), IQuoteRepository (GetItemsWithCoatsAsync
with CatalogItem eager load + AsNoTracking), and IJobRepository.GetOrphanedConversionJobAsync.

All EF complex include chains relocated into repository methods; controllers now
call named query methods rather than composing raw IQueryable chains.

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

src/PowderCoating.Core/Interfaces/IUnitOfWork.cs

@@ -22,7 +22,9 @@ public interface IUnitOfWork : IDisposable
     IRepository<JobDailyPriority> JobDailyPriorities { get; }
     IRepository<JobItem> JobItems { get; }
     IRepository<JobItemCoat> JobItemCoats { get; }
+    IRepository<JobItemPrepService> JobItemPrepServices { get; }
     IRepository<JobChangeHistory> JobChangeHistories { get; }
+    IRepository<JobPrepService> JobPrepServices { get; }
     IQuoteRepository Quotes { get; }
     IRepository<QuotePhoto> QuotePhotos { get; }
     IRepository<QuoteItem> QuoteItems { get; }
@@ -87,8 +89,8 @@ public interface IUnitOfWork : IDisposable
     IRepository<BillPayment> BillPayments { get; }
     IRepository<Expense> Expenses { get; }
 
-    // Notifications
-    IRepository<NotificationLog> NotificationLogs { get; }
+    // Notifications — typed repository for IgnoreQueryFilters-based history lookups
+    INotificationLogRepository NotificationLogs { get; }
     IRepository<NotificationTemplate> NotificationTemplates { get; }
 
     // Subscription