Execute a deposit transaction for Jupiter Borrow. Creates collateralized position. Specify positionId to use existing position or leave blank to create new.
Important: This endpoint behaves differently based on the position ID parameter:
With Position ID: Deposits into the specified existing position
Without Position ID: Creates a new position (does NOT auto-reuse empty positions)
To use an existing position, first fetch the user’s positions and provide the position ID. To create a new position, simply leave the position ID parameter empty.
This is for Jupiter Borrow (collateralized lending positions). For non-collateralized lending, use the Jupiter Earn endpoints.
