What does ignoring an invalid edit actually mean

**Link to problem area**: https://spec.matrix.org/v1.17/client-server-api/#validity-of-replacement-events

**Issue**

The spec says

> If any of these criteria are not satisfied, implementations should ignore the replacement event (the content of the original should not be replaced, and the edit should not be included in the server-side aggregation).

The brackets appear as an explainer as to what `ignore the replacement event` means - but they do not explain whether the entire event should be ignored, or just its replacement properties, and it still be rendered as a standalone event not referencing the event it tried to edit.

It'd be nice if the spec was more clear & explicit in whichever direction here

Start with the “Validity of replacement events” section at the linked Matrix specification entry point, then read the surrounding replacement-event rules. Clarify whether an invalid edit is omitted entirely or rendered as a standalone event, and make the section explicitly state the resulting behavior.

Written by the indexing model from the issue text.