Add customers management module with database schema and validation

- Introduced `CustomersModule` to manage customer data, including read and write controllers.
- Created database migrations for the `customers` and `customer_contacts` tables, including constraints and unique indexes.
- Implemented validation for customer fields such as name, code, and address with corresponding utility functions.
- Developed service and repository layers for handling customer data operations.
- Added unit tests for the customers service, repository, and controllers to ensure functionality and correctness.
- Updated application module to include the new `CustomersModule` for better organization.

drizzle/migrations/meta/_journal.json

@@ -43,6 +43,13 @@
       "when": 1787549883658,
       "tag": "0005_past_vengeance",
       "breakpoints": true
+    },
+    {
+      "idx": 6,
+      "version": "7",
+      "when": 1787554000000,
+      "tag": "0006_customers",
+      "breakpoints": true
     }
   ]
 }