new api service and logic implemented

Ztest/fixtures.py

@@ -0,0 +1,13 @@
+"""Test fixtures and models."""
+
+from sqlalchemy import Column, String
+
+from Services.PostgresDb.Models.mixins import CrudCollection
+
+
+class TestUser(CrudCollection):
+    """Test user model for PostgreSQL tests."""
+
+    __tablename__ = "test_users"
+    username = Column(String, unique=True, index=True)
+    email = Column(String, unique=True, index=True)