gh-155102: Preserve TypeError raised during set discard/remove comparison

[BHUVANSH855]

Fixes issue gh-155102.

set.discard() and set.remove() could incorrectly suppress or replace
exceptions raised during equality comparison when the lookup key was a
hashable subclass of set.

The issue was caused by the special set/frozenset fallback path treating
all TypeError cases from hashing as unhashable-key handling. This could
clear an exception raised by __eq__ and retry the lookup, resulting in
different behavior compared to normal membership testing.

This change separates the hash failure path from comparison errors:

• Preserve the existing fallback behavior for unhashable set/frozenset
  keys.
• Propagate exceptions raised during equality comparison consistently from
  set.discard() and set.remove().

A regression test has been added to cover a hashable set subclass whose
__eq__ raises TypeError.

Tests:

• ./python -m test test_set

[ZeroIntensity]

See my comment.