Follow-up to the #95605 salvage, closing the review findings:
- _copy_alias no longer swallows OSError silently: it warns (a leftover
alias symlink is the exact #95541 crash shape) and reports failure.
- Alias staging uses mkstemp (unique names) so concurrent ensures
(update + doctor --fix) can never promote a truncated interim copy.
- The anchor marker is written LAST and atomically (write-then-rename):
it now asserts the whole layout (anchor + aliases) is complete, so a
partially-materialized alias set can never read 'active' in doctor —
the next ensure retries the install instead.
- /.hermes-runtime/python/ store marker is derived from
managed_uv._RUNTIME_DIR_NAME instead of a hardcoded string.
5 new regression tests.
kshitijk4poor
0976ceaa98