City model added.

pos_api_app/models/city.py

@@ -0,0 +1,43 @@
+from django.db import models
+from django.contrib.auth.models import User
+
+class City(models.Model):
+    # Name of the city, e.g., "Istanbul", "Los Angeles"
+    name = models.CharField(max_length=150)
+
+    # Foreign key to the Country model, mandatory since every city belongs to a country
+    country = models.ForeignKey('Country', on_delete=models.CASCADE, related_name='cities')
+
+    # Foreign key to the State model, optional since not all countries have states
+    state = models.ForeignKey('State', on_delete=models.SET_NULL, null=True, blank=True, related_name='cities')
+
+    # Postal code for the city
+    postal_code = models.CharField(max_length=20, null=True, blank=True)
+
+    # Time zone(s) for the city, which may differ within states or regions
+    time_zones = models.JSONField(null=True, blank=True)
+
+    # Population of the city
+    population = models.IntegerField(null=True, blank=True)
+
+    # Indicates if the city has been marked as deleted (soft delete)
+    is_deleted = models.BooleanField(default=False, null=True)
+
+    # Description or reason for why the city was deleted
+    delete_description = models.TextField(null=True, blank=True)
+
+    # Foreign key to the User model, represents the user who created this city record
+    created_by = models.ForeignKey(User, related_name='city_created', on_delete=models.SET_NULL, null=True, blank=True)
+
+    # Automatically set when the city record is created
+    created_at = models.DateTimeField(auto_now_add=True)
+
+    # Foreign key to the User model, represents the user who last updated this city record
+    updated_by = models.ForeignKey(User, related_name='city_updated', on_delete=models.SET_NULL, null=True, blank=True)
+
+    # Automatically set when the city record is updated
+    updated_at = models.DateTimeField(auto_now=True)
+
+    class Meta:
+        db_table = 'City'
+        unique_together = ('name', 'country', 'state')  # Prevent duplicate city names in the same state or country