Massively Reduce Repo Code via DBOS

Identify an opportunity to massively reduce the amount of code (lines of code) in any part of the repo: - Similar functionality that can be unified and reused - Code that has been valuable but no more - Front end component or group of them duplicates another component functionality. Use the most modern and nice looking - Move to DBOS and get rid of supporting functionality relying on DBOS - etc. Implement it

Merged #4610: web console refactor, −303 net lines (no intended visual change; visual check passed) — shared auth entry-page components, one tone-colour map, shared Fact tiles, credential-tree aliases, dead exports. Full gate green. Deferred: DBOS outbox moves (ADR-0074), auth/credential backend dedup (security gate).