feat: unified document inbox, full BAS 2026, and document-transaction matching

- Expand BAS reference from ~180 to ~1,276 accounts (full BAS Kontoplan 2026)
  with K2 exclusion flags, per-class data files, and computed SRU codes
- Evolve invoice inbox into unified document inbox handling invoices, receipts,
  and government letters with AI-powered classification (Claude Haiku Vision)
- Add multi-pass document-to-transaction matching engine with greedy assignment
  for both supplier invoices (reference/amount/date/name) and receipts
  (weighted amount/merchant/date scoring)
- Add supplier invoice matching in transaction ingest pipeline
- Inject booking template suggestions into AI extraction prompts
- Surface matched documents in swipe categorization UI with one-tap booking
- Auto-activate missing BAS accounts during SIE import against full reference
- Add K2 filter toggle in Chart of Accounts manager
- Add receipt confirmation route with BFNAR representation fields
- Add database migrations for K2 support and document matching columns
- Remove obsolete extension migration scripts

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

app/api/transactions/[id]/categorize/route.ts

@@ -159,11 +159,17 @@ export async function POST(
     const template = getTemplateById(body.template_id)
     if (template) {
       finalCategory = is_business ? template.fallback_category : 'private'
+      console.log(`[categorize] tx=${id} using template="${body.template_id}" (${template.name_sv}) → category=${finalCategory}, debit=${template.debit_account}, credit=${template.credit_account}, vat=${template.vat_treatment}`)
     } else {
       return NextResponse.json({ error: 'Invalid template_id' }, { status: 400 })
     }
   } else {
     finalCategory = is_business ? (category || 'uncategorized') : 'private'
+    console.log(`[categorize] tx=${id} using category="${finalCategory}" vat=${body.vat_treatment || 'default'} account_override=${body.account_override || 'none'}`)
+  }
+
+  if (body.inbox_item_id) {
+    console.log(`[categorize] tx=${id} will confirm inbox item=${body.inbox_item_id} and link document`)
   }
 
   // Build mapping result from template or category
@@ -185,6 +191,12 @@ export async function POST(
     )
   }
 
+  console.log(`[categorize] tx=${id} mapping result:`, {
+    debit: mappingResult.debit_account,
+    credit: mappingResult.credit_account,
+    vatLines: mappingResult.vat_lines.map((v) => `${v.account_number} debit=${v.debit_amount} credit=${v.credit_amount}`),
+  })
+
   // Apply account override if provided (only for business transactions)
   if (is_business && body.account_override) {
     // Validate the account exists in the user's chart of accounts
@@ -287,6 +299,36 @@ export async function POST(
     }
   }
 
+  // Confirm matched inbox item and link its document to the journal entry
+  if (body.inbox_item_id) {
+    try {
+      await supabase
+        .from('invoice_inbox_items')
+        .update({ status: 'confirmed' })
+        .eq('id', body.inbox_item_id)
+        .eq('user_id', user.id)
+
+      // Link inbox item's document to the journal entry
+      if (journalEntryId) {
+        const { data: inboxItem } = await supabase
+          .from('invoice_inbox_items')
+          .select('document_id')
+          .eq('id', body.inbox_item_id)
+          .single()
+
+        if (inboxItem?.document_id) {
+          await supabase
+            .from('document_attachments')
+            .update({ journal_entry_id: journalEntryId })
+            .eq('id', inboxItem.document_id)
+            .eq('user_id', user.id)
+        }
+      }
+    } catch (inboxErr) {
+      console.error('[categorize] Failed to update inbox item:', inboxErr)
+    }
+  }
+
   // Update the transaction
   const { error: updateError } = await supabase
     .from('transactions')

app/api/transactions/suggest-categories/route.ts

@@ -137,6 +137,51 @@ export async function POST(request: Request) {
     template_suggestions[tx.id] = await getSuggestedTemplates(tx as Transaction, entityType)
   }
 
+  // Inject document template suggestions from matched inbox items
+  try {
+    const { data: matchedInboxItems } = await supabase
+      .from('invoice_inbox_items')
+      .select('matched_transaction_id, suggested_template_id, suggested_template_confidence')
+      .eq('user_id', user.id)
+      .in('matched_transaction_id', ids)
+      .not('suggested_template_id', 'is', null)
+
+    if (matchedInboxItems && matchedInboxItems.length > 0) {
+      console.log(`[suggest-categories] Found ${matchedInboxItems.length} matched inbox items with template suggestions`)
+      const { getTemplateById } = await import('@/lib/bookkeeping/booking-templates')
+
+      for (const item of matchedInboxItems) {
+        const txId = item.matched_transaction_id as string
+        const templateId = item.suggested_template_id as string
+        const template = getTemplateById(templateId)
+        if (!template) {
+          console.log(`[suggest-categories] Template "${templateId}" not found, skipping`)
+          continue
+        }
+
+        console.log(`[suggest-categories] Injecting document template: tx=${txId} → ${templateId} (${template.name_sv}, debit=${template.debit_account}, confidence=${item.suggested_template_confidence})`)
+
+        // Add to template_suggestions at the top with boosted confidence
+        const existing = template_suggestions[txId] || []
+        const docTemplate: SuggestedTemplate = {
+          template_id: templateId,
+          name_sv: template.name_sv,
+          name_en: template.name_en,
+          group: template.group,
+          debit_account: template.debit_account,
+          credit_account: template.credit_account,
+          confidence: Math.min((item.suggested_template_confidence as number) || 0.8, 1),
+          description_sv: template.description_sv,
+          risk_level: template.risk_level,
+          requires_review: template.requires_review,
+        }
+        template_suggestions[txId] = [docTemplate, ...existing.filter((t) => t.template_id !== templateId)]
+      }
+    }
+  } catch {
+    // Non-blocking
+  }
+
   // Trigger on-demand AI categorization for transactions with weak suggestions
   if (needsAiIds.length > 0) {
     console.log(