The tree walk counted only list, tuple and dict, so a codec whose tree used deque,
mappingproxy or another abc container was unbounded. Every Mapping, Sequence and Set
that is not text or bytes now counts. RecursionError from a user encode or decode,
and from the JSON decoder, reaches the caller as itself with its traceback; only
msgpack's StackError (raised by depth alone) is mapped to the depth refusal.
All commits build.
Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>
7f6649f9a1