feat(esh-ml1): wire telemetry and monitoring; fix Dozzle's stale agent list

- Beszel: NVIDIA agent (stacks/beszel hosts/esh-ml1.yaml), hub system
  registered with Status/Disk/CPU/Memory/Temperature alerts; GPU samples
  verified (RTX 2000E Ada util, VRAM, power, temp).
- Uptime Kuma: health monitors for the TEI embed (:8001) and rerank (:8013)
  services — the sole backends behind the gateway, so the one exception to
  "seats are out of Kuma's lane". Reward seat excluded (no consumer).
- Homepage: dockerd on tcp/2375 bound to 10.0.50.80 (playbook step);
  esh-ml1-docker added to docker.yaml.
- Dozzle: agent v10.4.1 on esh-ml1. The hub's DOZZLE_REMOTE_AGENT still
  named ana-ml2's 10.250.50.54 and irv-ml1's retired 10.100.79.3; repointed
  to 10.251.50.54 / 10.6.110.50 (fv-ml1 and irv-ml1 logs were missing).
- Documented nh3-dev's Beszel agent failing on NH3 cold start (bind of an
  automounted NAS share); revived by hand, fix still open.

stacks/uptimekuma/monitors.yaml

@@ -92,6 +92,21 @@ monitors:
   - name: Asset Engine
     url: http://10.250.50.70:8200/api/v1/services
 
+  # ---- fleet embed/rerank: the one EXCEPTION to "seats are OUT" ----
+  # Since 2026-09-25 these are the SOLE backends behind the gateway's
+  # `qwen3-embedding` and `reranker` (TEI on esh-ml1, no failover until the second
+  # RTX 2000 arrives). They are not come-and-go seats: dead = Worldtree recall,
+  # nevermore clustering and Open WebUI RAG all fail. TEI's /health runs the
+  # backend, so a loaded-but-broken model reads DOWN, not UP. The reward seat on the
+  # same box stays OUT: it has no working consumer (stacks/reward-seat/README.md).
+  - name: Embed — Qwen3 0.6B (TEI, esh-ml1)
+    url: http://10.0.50.80:8001/health
+    description: sole backend for gateway `qwen3-embedding`
+
+  - name: Rerank — bge-v2-m3 (TEI, esh-ml1)
+    url: http://10.0.50.80:8013/health
+    description: sole backend for gateway `reranker`
+
   - name: talk
     url: https://talk.nh3.phasefinal.com:8092/
     description: fleet voice bench