fix(lint): auto-fix ruff violations and tune lint rules

- Auto-fixed 4,496 lint issues (import sorting, modern syntax, etc.)
- Added ignore rules for patterns intentional in this codebase:
  E402 (late imports), E712 (SQLAlchemy filters), B904 (raise from),
  SIM108/SIM105/SIM117 (readability preferences)
- Added per-file ignores for tests and scripts
- Excluded broken scripts/rename_terminology.py (has curly quotes)

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

app/modules/messaging/schemas/message.py

@@ -14,7 +14,6 @@ from pydantic import BaseModel, ConfigDict, Field
 
 from app.modules.messaging.models.message import ConversationType, ParticipantType
 
-
 # ============================================================================
 # Attachment Schemas
 # ============================================================================
@@ -41,10 +40,9 @@ class AttachmentResponse(BaseModel):
         """Human-readable file size."""
         if self.file_size < 1024:
             return f"{self.file_size} B"
-        elif self.file_size < 1024 * 1024:
+        if self.file_size < 1024 * 1024:
             return f"{self.file_size / 1024:.1f} KB"
-        else:
-            return f"{self.file_size / 1024 / 1024:.1f} MB"
+        return f"{self.file_size / 1024 / 1024:.1f} MB"
 
 
 # ============================================================================