Update Content model to enforce status choices and add migration for status field changes

- Introduced STATUS_CHOICES in the Content model to restrict the status field to 'draft', 'review', and 'published'.
- Created a new migration to reflect the updated status choices without altering existing data.
- Removed 'completed' status from the frontend status color mapping for consistency.

backend/igny8_core/modules/writer/models.py

@@ -106,7 +106,12 @@ class Content(SiteSectorBaseModel):
     secondary_keywords = models.JSONField(default=list, blank=True, help_text="List of secondary keywords")
     tags = models.JSONField(default=list, blank=True, help_text="List of tags")
     categories = models.JSONField(default=list, blank=True, help_text="List of categories")
-    status = models.CharField(max_length=50, default='draft', help_text="Content workflow status (draft, review, published, etc.)")
+    STATUS_CHOICES = [
+        ('draft', 'Draft'),
+        ('review', 'Review'),
+        ('published', 'Published'),
+    ]
+    status = models.CharField(max_length=50, choices=STATUS_CHOICES, default='draft', help_text="Content workflow status (draft, review, published)")
     generated_at = models.DateTimeField(auto_now_add=True)
     updated_at = models.DateTimeField(auto_now=True)