Add/skv salary agi (#423)

* feat: add Bankgirot LB-fil support for salary payments and tax payments

- Implemented `generateBgLb` for salary batch payments, producing opening, payment, and closing records.
- Added tests for `generateBgLb` to ensure correct record generation and validation.
- Created `generateBankgiroPaymentBgLb` for single tax payments to Skatteverket, including validation and formatting.
- Added tests for `generateBankgiroPaymentBgLb` to verify record structure and data integrity.
- Introduced `generateSkattekontoOcr` for generating valid OCR references for Skattekonto payments, with tests for various input formats.
- Updated database schema to track payment file formats and timestamps for salary runs and AGI declarations.
- Created a new table for logging salary payslip deliveries to ensure compliance with audit requirements.

* feat: add write permission check and company ID validation for payment file generation

* feat: add write permission check for salary payment file generation

lib/api/schemas.ts

@@ -396,6 +396,8 @@ export const UpdateSettingsSchema = z.object({
   invoice_credit_terms_text: z.string().nullable().optional(),
   // AI agent flow
   ai_flow_enabled: z.boolean().optional(),
+  // Salary payment file
+  preferred_payment_format: z.enum(['bg_lb', 'pain001']).optional(),
 }).refine(
   (data) => {
     // BFL 3 kap.: Enskild firma must have fiscal year starting January