Current limitation: When DiagramShapeDefaultsEditable.Connect="true", users can draw connections between shapes, but there is no event fired when a new connection is created by the user.
Requested feature: Add OnConnectionCreated event that:

• Fires when user creates a new connection by dragging from one shape to another
• Returns event arguments containing:
  • FromShapeId — the source shape identifier
  • ToShapeId — the target shape identifier
  • Connection — reference to the newly created connection object (or its properties)
• Allows developers to intercept, validate, or customize the connection before it's finalized

Use case: We need to capture user-created connections to persist them to database, validate business rules (e.g., prevent circular dependencies), and set connection properties (type, label, color) based on context.