Bug/accounting suggestion (#456)

* feat: add bike benefit handling and optional vacation accrual

- Introduced bike benefit (cykelförmån) with calculations for annual market value and monthly taxable value.
- Updated schemas to include new benefit types and validation rules.
- Implemented API routes for creating, updating, and deleting employee benefits.
- Enhanced salary calculation logic to accommodate new vacation rule options, including a 'none' option for no accrual.
- Added UI components for managing employee benefits, including input for bike benefit specifics.
- Created database migrations for employee benefits and updated salary line items to support new benefit types.

* chore: remove Langfuse env var checks

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

* feat: enhance OAuth callback URL handling and update default scopes for Visma integration

* feat: remove trade_name field and simplify company naming in invoices

* refactor: destructure canWrite from useCanWrite for consistency across components

* feat: enhance PATCH endpoint to validate existing benefits and handle bike benefit updates

* feat: add missing label for bike benefit in salary line item types

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Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

components/transactions/JournalEntryPreview.tsx

@@ -90,12 +90,25 @@ export default function JournalEntryPreview({
       const vatRate = templateVatRate ?? 0
       const vatAmt = extractVatAmount(absAmount, vatRate)
       const netAmt = extractNetAmount(absAmount, vatRate)
+      const isIncome = amount > 0
 
-      result.push({ side: 'debet', account: templateDebitAccount, amount: netAmt })
-      if (vatAmt > 0) {
-        result.push({ side: 'debet', account: '2641', amount: vatAmt })
+      if (isIncome) {
+        // Income: debit bank gross, credit revenue net, credit output VAT
+        result.push({ side: 'debet', account: templateDebitAccount, amount: absAmount })
+        result.push({ side: 'kredit', account: templateCreditAccount, amount: netAmt })
+        if (vatAmt > 0) {
+          // Map rate → output VAT account (BAS 2611/2621/2631)
+          const outputVatAccount = vatRate === 0.06 ? '2631' : vatRate === 0.12 ? '2621' : '2611'
+          result.push({ side: 'kredit', account: outputVatAccount, amount: vatAmt })
+        }
+      } else {
+        // Expense: debit expense net + input VAT, credit bank gross
+        result.push({ side: 'debet', account: templateDebitAccount, amount: netAmt })
+        if (vatAmt > 0) {
+          result.push({ side: 'debet', account: '2641', amount: vatAmt })
+        }
+        result.push({ side: 'kredit', account: templateCreditAccount, amount: absAmount })
       }
-      result.push({ side: 'kredit', account: templateCreditAccount, amount: absAmount })
       return result
     }