rmm: host-migration runbook + ratified architecture (memory + pointer)

Bump guru-rmm pointer (host-migration runbook). Record the migration architecture
decision in memory: physical box becomes .30 (all-but-Gitea-runner), VM retired,
MariaDB migrates (backs the coord claudetools DB per Gate-A).

.claude/memory/MEMORY.md

@@ -23,6 +23,7 @@
 - [Gitea git-op latency](reference_gitea_git_op_latency.md) — SSH (.20:2222) is SLOWEST (~1.5s); internal HTTP+token ~0.55s; SOPS lookup only ~0.33s. Don't switch to SSH for speed. Gitea SSH is .20:2222 (API ssh_url .21 is wrong).
 - [GuruRMM technical reference](reference_gururmm.md) — Server (172.16.3.30) layout + downloads dir `/var/www/gururmm/downloads` + `.channel` sidecar rollout control (stable/beta) + privileged server access via the server's OWN root RMM agent (hostname `gururmm`, no SSH needed; plink fallback) + API + `context=user_session` (WTS impersonation) + build-pipeline vendoring at `deploy/build-pipeline/` + Linux agent systemd sandbox trap.
 - [RMM agent update model](rmm-agent-update-model.md) — Agent updates are server-PUSH on heartbeat (no self-poll); available versions = filesystem scan needing a `.sha256`; promote flips `.channel` sidecars beta→stable globally. Two stranders: beta-first freezes stable until an explicit promote; agents older than ~0.6.50 re-enroll with a NEW device_id/agent row when updated.
+- [GuruRMM physical server storage](gururmm-physical-server-storage.md) — New box 172.16.1.231 (temp IP→will be .30), Ubuntu 26.04, ssh key `gururmm-physical`/alias `gururmm-new`. SSD (915G root) = HOT (PG default tablespace + WAL + builds); HDD ext4 at `/data` = COLD (`gururmm_cold` PG tablespace for aged `agent_logs` partitions + downloads + backups + archive). The #3 retention answer.
 - [Trebesch DESKTOP-QNP3ON5 shell replacement](reference_trebesch_qnp3on5.md) — AT Trebesch box runs an Explorer shell replacement; explorer.exe owner check returns blank — use Win32_ComputerSystem.UserName. GuruRMM SWIFT-LION-2892.
 
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