The instance-pool reconnect() did disconnect() (nulling _sql) BEFORE connect(),
so a connect() failure during a transient Postgres blip left _sql null for the
rest of the process — every subsequent non-retry-wrapped call then fell through
to the never-connected module singleton and threw 'No database connection',
crashing the autopilot worker into a respawn loop. Build-then-swap: snapshot the
live pool, build a fresh one, end the old only once the new validates, restore
on failure. Keeps upstream's reap-detection + pool-recovery audit. Confirmed by
jalagrange on closed PR #1593; this is the Layer-1 fix he left to us.
Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
