AA (or any other airline) going Chapter 11: AA miles will still be honoured, but I would expect (true for all frequent flier programs/-miles at this difficult airline industry times) more devalutaion of miles (more miles needed for awards, less and more restrictive avilability for awards and upgrades).

AA (or any other airline) going chapter 7:
There is no legal obligation to honour any tickets issued by an airline or that airline's frequent flier program (ticket stock of that airline) after chapter 7.

Even when AN went bankrupt, SQ/AZ and other *-carriers were very reluctant (and did let more than a week go by) until they decided to honour (for goodwill reason, no legal obligation) tickets that were already booked/confirmed with them.

Unfortunately a bankruptcy of UA or AA or DL (or their ff-programs) would be of such a big dimension, that other carriers could probably not help you/us out, the financial loss for them would be intolerable. (There is currently still an obligation for US-carriers to honourinner-US-flight. tickets of another bankrupt US-carrier for a fee of US$25 ... as long as space is available ...).