Feature request: non-blocking play_file()

Maybe an optional boolean argument whether to block on WAV playback or not? Would want corresponding function(s) to poll whether currently playing and to disable speaker without accessing protected elements.

Currently working around this with a few extra lines in the Dragon Drop game:
https://github.com/adafruit/Adafruit_Learning_System_Guides/tree/main/Macropad_Dragon_Drop
Not a pressing need, the workaround’s simple enough, just that it might make user-facing code less daunting by not having pylint directives in there and stuff. Thx.

Start with the play_file() entry point and compare its current behavior with the workaround in the linked Macropad_Dragon_Drop example. Determine how optional non-blocking playback, playback polling, and speaker disabling should be exposed without protected-element access; done means the requested public behavior is available and the existing workaround is no longer needed.

Written by the indexing model from the issue text.