Track completion in a `data_migrations` table. On startup the
migration checks if it has already been applied and skips the
SimpleFIN API calls entirely, avoiding the slow startup.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Runs once at startup after DB migrations. For each SimpleFIN
connection, re-discovers accounts from the API, groups by
institution, and splits connections that contain accounts from
multiple banks. Existing sync state and account mappings are
preserved.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>