feat: wire Zod validation into API routes, improve types and components

- Add 8 new Zod schemas (UpdateCustomer, UpdateSupplier, UpdateSupplierInvoice,
  UpdateAccount, BankUnlink, RunReconciliation, CorrectJournalEntry,
  EvaluateMappingRules) and wire validateBody() into 24 JSON-body API routes
- Remove redundant manual validation checks replaced by Zod
- Add comprehensive schema tests (222 tests)
- Improve type definitions in types/index.ts with expanded interfaces
- Refactor extension types (push-notifications, receipt-ocr) for cleaner imports
- Update transaction components (BatchCategorySelector, SwipeCategorizationView,
  QuickReviewDialog, VatTreatmentSelect) and invoice inbox workspace
- Add invoice-inbox utilities and type decoupling tests
- Fix NE-bilaga, SRU export, and invoice PDF template type usage
- Update CLAUDE.md with expanded architecture documentation

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

lib/email/resend.ts

@@ -2,9 +2,10 @@ import { Resend } from 'resend'
 
 // Default sender configuration
 // Using a fixed From address with dynamic Reply-To
-// From: "Företagsnamn via ERP Base" <fakturor@erp-base.se>
+// From: "Företagsnamn via ERP Base" <your-from@example.com>
 // Reply-To: user's company email from company_settings
-const DEFAULT_FROM_EMAIL = 'fakturor@arcim.io'
+// Set RESEND_FROM_EMAIL in .env.local to your verified Resend domain
+const DEFAULT_FROM_EMAIL = process.env.RESEND_FROM_EMAIL || 'noreply@localhost'
 
 // Lazy initialization to avoid errors at build time
 let resendClient: Resend | null = null