feat: add 4 new Swedish bank CSV parsers and improve transaction categorization

Add auto-detecting CSV parsers for Länsförsäkringar, ICA Banken, Skandia,
and Lunar. Refine SEB detection to avoid false matches. Update bank file
upload UI with new bank options and export instructions. Include booking
templates, improved AI categorization, and transaction review enhancements.

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

lib/bookkeeping/mapping-engine.ts

@@ -5,11 +5,13 @@ import {
   extractNetAmount,
   extractVatAmount,
 } from './vat-entries'
+import { findMatchingTemplates, buildMappingResultFromTemplate } from './booking-templates'
 import type {
   MappingRule,
   MappingResult,
   RiskLevel,
   Transaction,
+  EntityType,
   VatJournalLine,
 } from '@/types'
 
@@ -28,7 +30,8 @@ const CAPITALIZATION_THRESHOLD = 29400
  */
 export async function evaluateMappingRules(
   userId: string,
-  transaction: Transaction
+  transaction: Transaction,
+  entityType?: EntityType
 ): Promise<MappingResult> {
   const supabase = await createClient()
 
@@ -41,6 +44,9 @@ export async function evaluateMappingRules(
     .order('priority', { ascending: true })
 
   if (error || !rules || rules.length === 0) {
+    // Try template-based matching before default fallback
+    const templateResult = evaluateTemplateRules(transaction, entityType)
+    if (templateResult) return templateResult
     return getDefaultResult(transaction)
   }
 
@@ -51,9 +57,35 @@ export async function evaluateMappingRules(
     }
   }
 
+  // Try template-based matching before default fallback
+  const templateResult = evaluateTemplateRules(transaction, entityType)
+  if (templateResult) return templateResult
+
   return getDefaultResult(transaction)
 }
 
+/**
+ * Evaluate booking templates as a fallback when no DB mapping rule matches.
+ * Returns the best template match if confidence >= 0.3, otherwise null.
+ */
+function evaluateTemplateRules(
+  transaction: Transaction,
+  entityType?: EntityType
+): MappingResult | null {
+  const matches = findMatchingTemplates(transaction, entityType)
+  if (matches.length === 0 || matches[0].confidence < 0.3) return null
+
+  const best = matches[0]
+  const result = buildMappingResultFromTemplate(
+    best.template,
+    transaction,
+    entityType || 'enskild_firma'
+  )
+  // Override the confidence with the auto-match confidence (not 1.0)
+  result.confidence = best.confidence
+  return result
+}
+
 /**
  * Check if a transaction matches a mapping rule
  */