Buy at Open, close at Close of the same candlestick

Can you make it so we can buy at Open and close the position at Close the same candlestick?

Thanks

Start by tracing the backtesting engine's order-execution flow to determine how Open and Close prices are handled within one candlestick. Clarify the intended same-candle semantics and edge cases with maintainers before changing behavior; done requires an agreed implementation and coverage for the requested trade sequence.

Written by the indexing model from the issue text.