Second-round review on #132646 (F1-F10), each reproduced on 2531fb2 first:
- Moves are matched one-to-one: unchanged units are reserved first, then
same-file body, then cross-file body only when the origin's name is gone,
then same name. A copy of unchanged debt is new debt; a function moved
over a same-name stub keeps its own cap (F1, F3).
- Every base hit is owned by exactly one head scope, so a file rename no
longer counts each old hit twice (F2).
- Ruff runs when either side has Python, so a delete-only .py diff with a
TS edit no longer crashes on a missing ruff result (F4).
- Deadlines must be finite: timeout=None, **{} and asyncio.timeout(None)
are no deadline; awaited calls inside `async with asyncio.timeout(x)`
are bounded (F5, F8).
- HX005 walks only what runs at import: the import-time branch of a
`__name__` guard (either operator), loops, match, try*, decorators,
class bases; a lambda value is deferred (F9).
- `health: allow` counts only in real comment tokens (Python tokenize, TS
comment trivia), never in string literals (F7).
- TS function lines are owned by the innermost function, so siblings on
one line give it up once (F10).
- The pre-commit hook runs `scripts/check --staged`: health compares the
index tree, and when the working tree differs from the index the other
checkers run on a checkout-index copy with a copied index, so commits are
judged on the staged bytes and unstaged work is never touched (F6).
4f70e88c0e