feat: enhance supplier invoices, entity-aware categorization, and new tests

Expand supplier invoice module with overdue cron job, credit note journal
entries, and event emissions on approve/mark-paid/create flows. Add entity
type (EF/AB) awareness to transaction categorization UI and category
mapping logic. Add comprehensive tests for supplier-invoice-entries,
transaction-entries, and expanded API route coverage.

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

supabase/migrations/20240101000046_supplier_invoice_overdue_cron.sql

@@ -0,0 +1,30 @@
+-- Migration: supplier_invoice_overdue_cron
+-- Sets overdue status on supplier invoices past due_date via pg_cron
+
+-- Enable pg_cron extension
+CREATE EXTENSION IF NOT EXISTS pg_cron WITH SCHEMA pg_catalog;
+
+-- Grant usage to postgres role (required by Supabase)
+GRANT USAGE ON SCHEMA cron TO postgres;
+
+-- Function to update overdue supplier invoices
+CREATE OR REPLACE FUNCTION public.update_overdue_supplier_invoices()
+RETURNS void
+LANGUAGE plpgsql
+SECURITY DEFINER
+AS $$
+BEGIN
+  UPDATE supplier_invoices
+  SET status = 'overdue',
+      updated_at = NOW()
+  WHERE due_date < CURRENT_DATE
+    AND status IN ('registered', 'approved');
+END;
+$$;
+
+-- Schedule daily at 06:00 UTC (matches existing banking sync timing)
+SELECT cron.schedule(
+  'update-overdue-supplier-invoices',
+  '0 6 * * *',
+  $$SELECT public.update_overdue_supplier_invoices()$$
+);