chore: add min validation for isolated limit orders

[moo-onthelawn]

Add validation for isolated margin limit orders so that traders can't place orders <$20 total equity.

Renamed TradeMarketOrderInputValidator -> TradeOrderInputValidator

• Added const isolatedLimitOrderMinimumEquity = 20
• Added logic for validating that isolated margin limit orders (and stop limit and take profit limit) are using at least 20 dollars of equity by comparing post freeCollateral with current freeCollateral
  • Wrote 2 versions (one is statically typed, one isn't)
  • Error: ISOLATED_MARGIN_LIMIT_ORDER_BELOW_MINIMUM - add error for minimum isolated margin limit orders v4-localization#670

Added tests in V4TradeInputTests

I don't think our FE is reading in the link stuff rn, but willl dig in more. Here is proof of concept of it working:

validationError.mov

[linear]

CT-1142 abacus to return validation error