Only the initial SELECT of _dedupe_legacy_system_prompts was guarded;
a 'database is locked' on any per-row write propagated out, aborted
schema init, left the schema version below 25, and made every later
SessionDB.__init__ re-enter the same migration against the same
contended DB - the second half of the enterprise crash-loop report.
The per-row loop now catches OperationalError, logs once, and returns.
Partial migration is safe by design: the legacy system_prompt column
is the documented read fallback for unmigrated rows, and the next
schema init resumes where the contention stopped. Tests prove rows
migrated before the failure stay migrated, the remainder stays
readable, and a later run completes it.
Victor Kyriazakos
e997435004