feat: Introduces Char32UUIDField for model UUIDs

Adds a custom UUIDField to use 32-character format for IDs
to optimize database storage and integration with existing systems.
Refactors model definitions to replace default UUIDField with the
new Char32UUIDField to maintain consistent implementation across the codebase.

src/pix360core/fields.py

@@ -0,0 +1,11 @@
+from django.db import models
+
+class Char32UUIDField(models.UUIDField):
+    def db_type(self, connection):
+        return "char(32)"
+
+    def get_db_prep_value(self, value, connection, prepared=False):
+        value = super().get_db_prep_value(value, connection, prepared)
+        if value is not None:
+            value = value.hex
+        return value

src/pix360core/models/content.py

@@ -1,6 +1,8 @@
 from django.db import models
 from django.contrib.auth import get_user_model
 
+from ..fields import Char32UUIDField as UUIDField
+
 import mimetypes
 import uuid
 
@@ -27,7 +29,7 @@ class File(models.Model):
         is_result (BooleanField): Whether this file is the result of a conversion
     """
 
-    id = models.UUIDField(primary_key=True, default=uuid.uuid4)
+    id = UUIDField(primary_key=True, default=uuid.uuid4)
     file = models.FileField(upload_to=file_upload_path)
     mime_type = models.CharField(max_length=256, default="application/octet-stream")
     conversion = models.ForeignKey(to='Conversion', on_delete=models.SET_NULL, null=True, blank=True)
@@ -65,7 +67,7 @@ class Conversion(models.Model):
         log (TextField): Log of the conversion
     """
 
-    id = models.UUIDField(primary_key=True, default=uuid.uuid4)
+    id = UUIDField(primary_key=True, default=uuid.uuid4)
     title = models.CharField(max_length=256, null=True, blank=True)
     url = models.URLField()
     downloader = models.CharField(max_length=256, null=True, blank=True)