feat: Refactor rides app with unique constraints, mixins, and enhanced documentation

- Added migration to convert unique_together constraints to UniqueConstraint for RideModel.
- Introduced RideFormMixin for handling entity suggestions in ride forms.
- Created comprehensive code standards documentation outlining formatting, docstring requirements, complexity guidelines, and testing requirements.
- Established error handling guidelines with a structured exception hierarchy and best practices for API and view error handling.
- Documented view pattern guidelines, emphasizing the use of CBVs, FBVs, and ViewSets with examples.
- Implemented a benchmarking script for query performance analysis and optimization.
- Developed security documentation detailing measures, configurations, and a security checklist.
- Compiled a database optimization guide covering indexing strategies, query optimization patterns, and computed fields.

backend/apps/rides/models/rides.py

@@ -1,5 +1,6 @@
 from django.db import models
 from django.utils.text import slugify
+from django.core.exceptions import ValidationError
 from config.django import base as settings
 from apps.core.models import TrackedModel
 from apps.core.choices import RichChoiceField
@@ -165,8 +166,18 @@ class RideModel(TrackedModel):
 
     class Meta(TrackedModel.Meta):
         ordering = ["manufacturer__name", "name"]
-        unique_together = [["manufacturer", "name"], ["manufacturer", "slug"]]
         constraints = [
+            # Unique constraints (replacing unique_together for better error messages)
+            models.UniqueConstraint(
+                fields=['manufacturer', 'name'],
+                name='ridemodel_manufacturer_name_unique',
+                violation_error_message='A ride model with this name already exists for this manufacturer'
+            ),
+            models.UniqueConstraint(
+                fields=['manufacturer', 'slug'],
+                name='ridemodel_manufacturer_slug_unique',
+                violation_error_message='A ride model with this slug already exists for this manufacturer'
+            ),
             # Height range validation
             models.CheckConstraint(
                 name="ride_model_height_range_logical",
@@ -222,6 +233,14 @@ class RideModel(TrackedModel):
             else f"{self.manufacturer.name} {self.name}"
         )
 
+    def clean(self) -> None:
+        """Validate RideModel business rules."""
+        super().clean()
+        if self.is_discontinued and not self.last_installation_year:
+            raise ValidationError({
+                'last_installation_year': 'Discontinued models must have a last installation year'
+            })
+
     def save(self, *args, **kwargs) -> None:
         if not self.slug:
             from django.utils.text import slugify