[Fix][Android] Avoid blocking threads to prevent deadlocks

[frw]

Similar to #547, I've run into issues with main thread deadlocking when using this library to show a BiometricPrompt and have seen an increased rate of ANRs on Crashlytics.
Upon further digging it was due to react-native-reanimated attempting to acquire a lock on the main thread, but since this library waits on the JS thread for the BiometricPrompt to show and finish on the main thread, a deadlock occurs.
This library avoids blocking the JS thread by using a listener to resolve a promise when decryption finishes. Since there are no additional dependencies, this should be compatible up to API level 21.

This PR should fix #525

[androideveloper]

For reanimated related issues, please refer to this PR and thread software-mansion/react-native-reanimated#3440

[frw]

Thanks @androideveloper for referring me to that thread! Glad to know something is also being done on the reanimated side to fix it.
However, I think we should still consider fixing this thread-blocking behavior as well since it is not ideal to be blocking a thread while waiting for the biometrics prompt to finish. Would appreciate any comments or feedback on the PR!

[ca057]

I experienced the same issue and could resolve by using the version from this PR, all tests so far are successful. Is there anything I can support with to get this change / fix merged into upstream?

[frw]

@oblador Any chance you could take a look at this, seems like it's still affecting a few folks

[kabirbaidhya]

Any progress / blockers on this PR? Can we prioritize this?

[androideveloper]

Hi @frw! I'm going to have a look at your PRs in this repo. Did you already test these changes in a real app?

[androideveloper]

is handler not used anymore?

[DorianMazur]

Fixed in 9.0.0