Model property - stored in DB for display, get returns model_usage.model
IMPORTANT: This property should ONLY be used in these scenarios: - Database read/write operations (SQ framework) - UI display when only DB data is loaded (SessionPlaceholder)
For all other code, ALWAYS work with model_usage directly. Never set or read this property outside of the above scenarios.
When set, stores in model_usage_model (for DB persistence) When get, returns model_usage.model (not model_usage_model)