History was only fetched by the startup seed, so a Schwab outage stayed a
hole until the next deploy — Sept 9 to 24 after a refresh token expired.
A reconnect more than two minutes past the last bar now fetches the gap
from Yahoo, fills empty buckets only, refolds the live forming buckets,
rebuilds levels without alerting, and resyncs every socket.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
