Sweep all of v2/ through pre-commit (was previously only run on changed
files). Fixes surfaced across untouched modules:
- ruff: isinstance-tuple -> X | Y (UP038), try/except/pass ->
contextlib.suppress (SIM105), negated-return (SIM103), %-format ->
f-string (UP031).
- mypy: add annotations for no-untyped-call + var-annotated across recipes,
training methods, torch/toy backends, and serving.
- yapf reflow of the SF-Wan KV-cache call sites (semantics unchanged).
yapf/ruff/codespell/mypy all pass; v2 tests 237 passed / 5 pre-existing
(bucket_c torch-absent on CPU venv).
SolitaryThinker
21e59268d8