Add ReviewEvent model and ReviewSubmissionService for review management

- Created a new ReviewEvent model to track review events with fields for content, rating, moderation status, and timestamps.
- Added ForeignKey relationships to connect ReviewEvent with ContentSubmission, User, and Review.
- Implemented ReviewSubmissionService to handle review submissions, including creation, updates, and moderation workflows.
- Introduced atomic transactions to ensure data integrity during review submissions and updates.
- Added logging for review submission and moderation actions for better traceability.
- Implemented validation to prevent duplicate reviews and ensure only the review owner can update their review.

django/api/v1/schemas.py

@@ -467,58 +467,6 @@ class SubmissionListOut(BaseModel):
     total_pages: int
 
 
-# ============================================================================
-# Versioning Schemas
-# ============================================================================
-
-class EntityVersionSchema(TimestampSchema):
-    """Schema for entity version output."""
-    id: UUID
-    entity_type: str
-    entity_id: UUID
-    entity_name: str
-    version_number: int
-    change_type: str
-    snapshot: dict
-    changed_fields: dict
-    changed_by_id: Optional[UUID] = None
-    changed_by_email: Optional[str] = None
-    submission_id: Optional[UUID] = None
-    comment: Optional[str] = None
-    diff_summary: str
-
-    class Config:
-        from_attributes = True
-
-
-class VersionHistoryResponseSchema(BaseModel):
-    """Response schema for version history."""
-    entity_id: str
-    entity_type: str
-    entity_name: str
-    total_versions: int
-    versions: List[EntityVersionSchema]
-
-
-class VersionDiffSchema(BaseModel):
-    """Schema for version diff response."""
-    entity_id: str
-    entity_type: str
-    entity_name: str
-    version_number: int
-    version_date: datetime
-    differences: dict
-    changed_field_count: int
-
-
-class VersionComparisonSchema(BaseModel):
-    """Schema for comparing two versions."""
-    version1: EntityVersionSchema
-    version2: EntityVersionSchema
-    differences: dict
-    changed_field_count: int
-
-
 # ============================================================================
 # Generic Utility Schemas
 # ============================================================================