Allow signal entry bid-ask spread filter

If you check Allow signal override next to Entry bid-ask spread filter, then bidAskSpreadFilter in the webhook (when present) is used as the entry spread cap for that signal. If the key is omitted, the Entry bid-ask spread filter saved on the subscription is used.

If Allow signal overrides is enabled, bidAskSpreadFilter is also honored for entry planning even when Allow signal override for Entry bid-ask spread filter is unchecked.

Example:

{
    "ticker": "AAPL",
    "action": "buy",
    "orderType": "limit",
    "limitPrice": 150,
    "bidAskSpreadFilter": 0.02
}