docs(api): clarify replay uses current context tx

[gfischer7]

This change aligns replay-related API docs with runtime behavior, clarifying that replay executes the transaction currently stored in context.

[codspeed-hq]

Merging this PR will not alter performance

✅ 176 untouched benchmarks
⏩ 1 skipped benchmark¹

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_{Comparing gfischer7:replay-current-context-tx (e512b52) with main (f7ccd08)}

Footnotes

1. 1 benchmark was skipped, so the baseline result was used instead. If it was deleted from the codebase, click here and archive it to remove it from the performance reports. ↩