retry operators: validate | and & operands on both sync and async retry_base

[HrachShah]

What

The | and & operators on retry_base and async_retry_base
accept either a retry strategy or a plain callable. A non-callable
non-retry_base value (e.g. True | retry_always, retry & 42,
None & async_retry) used to silently build a retry_any or
retry_all whose __call__ later raised TypeError: '<type>' object is not callable (sync) or TypeError: object bool can't be used in 'await' expression (async) from inside the running retry
loop, far from the original misuse. The operators now raise a clear
TypeError naming the bad operand at the construction site, so
common typos like retry or True or True | async_retry fail fast
with an actionable message.

Where

• tenacity/retry.py: retry_base._validate_predicate (static
  method), called from __and__, __rand__, __or__, __ror__.
• tenacity/asyncio/retry.py: same guard added to
  async_retry_base.__and__, __rand__, __or__, __ror__,
  and to the leaf branches of retry_any.__ror__ and
  retry_all.__rand__ (which are reached when Python's reflected
  operator dispatch goes through the subclass's override rather than
  the base class's).

Tests

• 5 new sync tests in tests/test_tenacity.py::TestRetryConditions::test_retry_composition_rejects_non_callable
  covering True | retry, retry | False, retry & 42,
  "nope" | retry, and None & retry.
• 4 new async tests in tests/test_asyncio.py::TestAsyncRetryComposition:
  test_async_retry_composition_rejects_non_callable (mirrors the
  sync test with async operators), test_async_retry_composition_accepts_valid_operands
  (regression guard for valid compositions still building retry_any /
  retry_all), test_async_retry_any_ror_validates_leaf_operand and
  test_async_retry_all_rand_validates_leaf_operand (cover the
  subclass-operator leaf branches that don't go through
  async_retry_base\.__ror__ / __rand__).
• python3 -m pytest tests/ passes 171 tests (was 167).
• ruff check tenacity/asyncio/retry.py tenacity/retry.py clean.
• Verified manually: True | tenacity.retry_always raises
  TypeError: Retry predicates must be retry_base instances or callables, got bool: True; True | tenacity.asyncio.retry.retry_if_exception(lambda exc: True)
  raises the same; legitimate compositions
  async_retry | sync_retry, async_retry | async_retry,
  async_retry | lambda still build a retry_any with the
  expected operands.

Release notes

releasenotes/notes/reject-non-callable-retry-operands-7c4e9f2b1a3d8c5e.yaml
(sync, added previously) and
releasenotes/notes/fix-async-retry-composition-validates-operand-8f3a2b1e6c4d9a72.yaml
(async, this commit) per the project's reno convention.

[jd]

unrelated

Pull request has been modified.