Ad-hoc quote email, accounting improvements, AI lookup fix, and misc service updates

- Quotes: ad-hoc email modal on Quote Details lets staff send to an address not on file;
  QuotesController passes overrideEmail through to NotificationService
- Quotes/Details view: SMS consent display, email/SMS send button state based on consent
- Accounting module: AccountingDisplayHelpers for consistent ledger formatting;
  AccountsController + Accounts views improvements; AccountingEnums additions
- Bills/Expenses: AI account categorization fixes in BillsController and ExpensesController
- InventoryAiLookupService: TDS cure fallback no longer fires on AiAugmentFromUrl path
  (LookupByUrlAsync already has it built in — was double-fetching)
- PdfService: quote/invoice PDF updates
- PricingCalculationService: minor pricing logic fix
- QuoteProfile: mapping updates for new quote fields
- ApplicationDbContextModelSnapshot: catches up to all 4 migrations in this branch

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

src/PowderCoating.Web/Helpers/AccountingDisplayHelpers.cs

@@ -0,0 +1,17 @@
+using System.Text.RegularExpressions;
+using PowderCoating.Core.Enums;
+
+namespace PowderCoating.Web.Helpers;
+
+public static class AccountingDisplayHelpers
+{
+    // Splits at lowercase→uppercase boundaries: "AccountsReceivable" → "Accounts Receivable"
+    private static readonly Regex _camelSplit =
+        new(@"(?<=[a-z])(?=[A-Z])", RegexOptions.Compiled);
+
+    public static string ToDisplayName(this AccountSubType subType) =>
+        _camelSplit.Replace(subType.ToString(), " ");
+
+    public static string ToDisplayName(this AccountType accountType) =>
+        _camelSplit.Replace(accountType.ToString(), " ");
+}