Add Close Long Zap

[DannyDelott]

• Switch to zap-based preview function when closing long to non-base/shares token (code to look at isZapping, and enable the correct query)
• Approve zap contract to spend your Longs in the event of close long zap
• Switch to zap-based write function

[DannyDelott]

Tracer bullets in sandbox, @jackburrus is going to add them to the UI

[DannyDelott]

Field trip into the Portfolio to make sure the events are properly working to display zapped/partially zapped positions. Currently balanceOf is returning a value, but the sdk's getOpenLongDetails is returning 0.

[DannyDelott]

Example script now runs with a complete workflow of opening a long and closing it with a zap #1773