Post-merge follow-up to #71770. Both defects were found by @helix4u in review
and reproduced against merged main before fixing.
1. Check/use race in _copy_source_bundle (my bug, from the #71770 follow-up
commit). It called has_live_connection(), released the registry lock, and
only then ran shutil.copy2() over the bundle. A tracked connection could
open in that window; the copy's close() then cancels its POSIX advisory
locks -- the exact class #71724 closed. Measured on main: a racer thread
opened a connection mid-copy after blocking 0.000s.
Adds sqlite_safe_read.offline_file_access(), a context manager that holds
the connection-lifecycle lock across an entire multi-step raw access, and
routes the bundle copy through it. Same racer now blocks 10.0s until every
raw descriptor is closed. Any future raw read of a database file (hashing,
moving a bundle aside) should use this rather than a bare pre-check.
2. _copy_state_meta_salvage assumed a 'key' column. A damaged state_meta can
keep 'value' and lose 'key'; columns.index("key") then raised ValueError
and aborted the whole partial recovery. The mirror case (key without
value) would have copied key-only rows and reported the table complete.
Now requires both, matching the non-partial _copy_state_meta, so an
unusable optional table is recorded as missing/failed and --allow-partial
still recovers sessions and messages.
Both regression tests verified by sabotage: reinstating the bare pre-check
fails the race test, removing the key/value requirement fails the other.
937 targeted tests green.
teknium1
9657f6e343