plans: rename resident agent Hermes -> Nomos, add implementable rename phase N0

Nomos (from oikonomos, steward of the oikos) avoids the name collision
with Nous Research's Hermes Agent. N0 enumerates the full rename scope:
cmd/, hermes/ dir, env vars, config fields, compose service, Caddy vhost,
identity-preserving DB slug migration + seed update, persona docs.
History, the Matrix bot user, and legacy bin/hermes stay untouched.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

plans/2026-07-08-control-room-webui.md

@@ -116,12 +116,12 @@ Persistent nav + live top status strip (health dots, open-signal badge,
 pending-approval badge):
 
 0. **Agent chat (home view)** — *amendment 2026-07-08, see the
-   [Hermes resident agent plan](2026-07-08-hermes-resident-agent.md)*: the
-   default view at `/ui/#/` is a conversation with the resident Hermes agent
-   (streamed via `/agent/chat`), with a live right rail showing pending
-   approvals (decidable in place), recent events, and health. A persistent
-   chat drawer is reachable from every other page. Lands with resident-agent
-   milestone H3; until then, Overview is the home view.
+   [Nomos resident agent plan](2026-07-08-nomos-resident-agent.md)*: the
+   default view at `/ui/#/` is a conversation with the resident Nomos agent
+   (formerly Hermes; streamed via `/agent/chat`), with a live right rail
+   showing pending approvals (decidable in place), recent events, and health.
+   A persistent chat drawer is reachable from every other page. Lands with
+   resident-agent milestone N3; until then, Overview is the home view.
 1. **Overview** — summary cards from `/dashboard/summary`, event-rate
    sparkline, live event ticker, top degraded entities.
 2. **Graph explorer** — d3-force over `/graph`; node color = health; filters