Recipient check debounce may have regressed to per-keystroke

[Jaydbrown]

After the recent merges, confirm checkRecipientExists still fires once per 600ms of idle, not on every keystroke, and that the in-flight check is aborted when the address changes.

[69starman]

@69starman has applied to work on this issue as part of the Stellar Wave Program's 8th wave.

Hello sir maintainer....
I have a vast experience in solving github issues ...
Please do well to assign me this let me get it done for you ✅.
Thank you 😊

ℹ️ Repo Maintainers: To accept this application, review their application or assign @69starman to this issue.

[Timmmytunner]

@Timmmytunner has applied to work on this issue as part of the Stellar Wave Program's 8th wave.

Hello Maintainer, I’ve reviewed the issue and understand the requirements. I’m confident I can handle the task effectively and would appreciate the opportunity to work on it.

ℹ️ Repo Maintainers: To accept this application, review their application or assign @Timmmytunner to this issue.

[Baytizz]

@Baytizz has applied to work on this issue as part of the Stellar Wave Program's 8th wave.

I have reviewed the issue and i would like to work on it. I am confident that I can get it fixed perfectly if I get assigned to work on it

ℹ️ Repo Maintainers: To accept this application, review their application or assign @Baytizz to this issue.