Add customergroup and entity HTTP APIs with address and contact routes.

Expose store-backed CRUD for customer groups, entities, nested addresses, and contacts, matching the documented dashdbschema contracts.

scripts/generateApiDocs.js

@@ -38,6 +38,8 @@ const options = {
             { name: 'Brand', description: 'Company-scoped brands' },
             { name: 'Supplier', description: 'Company-scoped suppliers (Lieferanten)' },
             { name: 'Delivery', description: 'Company-scoped goods receipts (Lieferungen)' },
+            { name: 'Customergroup', description: 'Company-scoped customer groups' },
+            { name: 'Entity', description: 'Company-scoped entities, addresses, and contacts' },
             { name: 'Image', description: 'Content-addressed AVIF by fullHash' },
             { name: 'Posterminal', description: 'Company-scoped POS terminals' },
         ],