Audit 37 stale common_grid_slugs flagged by Relay N4b backfill

Talos ran N4b reconciler in prod (2026-05-09 17:30 UTC, #agent-ops thread). 798/835 crm_organizations got eia_utility_id populated via CommonGrid /utilities/{slug}. The remaining 37 returned 404. Need to: (1) enumerate the 37 stale slugs (Talos has the list — ping in #agent-ops if not), (2) classify each: renamed (add slug alias), retired/merged (verify in /api/v1/utilities/deprecated and possibly add successor mapping), or genuinely bad data on Relay side. (3) For renamed utilities, add slug_aliases entries in CommonGrid so old slugs resolve. (4) Report back to Talos with disposition. This unblocks NISC linkage for any orgs whose Relay slug is stale.