Clear signal requestID on workflow close

[dhiaayachi]

Is your feature request related to a problem? Please describe.
Signal requestID is for dedupping signal request. After workflow close, all signal requests will be rejected, so we don't really need signal requestIDs for dedupping.

Describe the solution you'd like

• Clear signal requestID on workflow close
• However, we may need it for Signal requestID dropped upon workflow reset temporalio/temporal#4028. If that's the case, we can persist the requestID as part of the signaled event, so that upon reset, the signal requestID map can be rebuilt.

Describe alternatives you've considered

• We don't have to do it if we believe we won't benefit much from making this change.

Additional context
Add any other context or screenshots about the feature request here.

[dhiaayachi]

Thank you for your feature request! This is a great idea and would definitely be useful for many users.

While we don't have a specific plan to implement this feature right now, you can work around it by persisting the signal request ID as part of the signaled event. This way, upon reset, the signal request ID map can be rebuilt.

Let me know if you have any other questions.