docs(framework): field lessons + session close-out for pfv-bms stabilization [#344]

AGENTS.md

@@ -270,6 +270,24 @@ Hard-won operational gotchas. One line each; keep them short and load-bearing.
   REST API (`/api/`, `/api/config`, `/api/services`) with the long-lived
   token in `~/.creds/homeassistant.env`. Instance unit system is °F — set
   explicit `unit_of_measurement: "°C"` on custom sensors.
+- **HAOS core_ssh on 22222 is the sanctioned host shell:** `VM_IP=pfv-bms-lan.knel.net
+  VM_USER=root VM_PORT=22222 bash tests/remote.sh vm '...'` — use the LAN name
+  (knel.net zone is Tailscale-IP based; TS inbound to pfv-bms is unreliable).
+  Host OS has NO git/ssh/curl — run git against /mnt/data/supervisor/homeassistant
+  via `docker run homeassistant/amd64-addon-git_pull:<ver>`.
+- **Git pull add-on (core_git_pull) wipes /config on first run** if `.git` is
+  absent (rm -rf + fresh clone). ALWAYS pre-seed /config as a git checkout
+  (deploy key ~/.creds/pfv-bms-gitpull, repo KNEL/pfv-bms) before starting it.
+- **HA core boot death-spiral:** supervisor watchdog SIGTERMs slow boots
+  (docker logs: "finish process received signal 15" while supervisor logs
+  "Still waiting for Core to start"). Fix from the 22222 shell:
+  `ha ha options --watchdog=false`, start core, diagnose, re-enable once stable.
+- **Technitium on netinfra-02 (tsys-dns container) does not reload rsync-synced
+  zone files** — `docker restart tsys-dns` after record adds until #469 (native
+  clustering) lands. netinfra-01 (the dns-cli target) is fine.
+- **Supervisor add-on options via API:** docker cp a script into
+  hassio_supervisor, read token from /data/cli.json `access_token`, POST
+  /addons/<slug>/options (the /apps/ spelling 404s).
 
 ## Questions (NON-NEGOTIABLE)