Enhanced Take-profit and Stop-loss inputs

Users have repeatedly voiced the need for easier TP/SL inputs.

Those inputs should at minimum have buttons like the Limit and Stop price inputs (+1%, +2%, etc.) and also show the P/L amount and P/L percent corresponding to the user's input.

Ideally, we should find a UX that lets the user input price, percent, or P/L amount for both TP and SL. Currently, the user can only input price.

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