docs: record PD Pi-hole retirement state

docs/planning/TODO.md

@@ -5,9 +5,9 @@
 - [x] Regenerate N.O.M.A.D. Newt secret (was exposed in chat) — completed 2026-05-15
 
 ## Infrastructure
-- [x] Deploy Pi-hole HA on PD + N.O.M.A.D. with VIP `10.5.30.53` — completed 2026-05-15; historical Trusted-VLAN design, later superseded after NOMAD moved to Servers (`10.5.30.7`) and its Trusted-side Keepalived role was disabled pending a same-subnet HA redesign; see docs/planning/DEPLOY_PIHOLE.md
-  - PD primary live at `/mnt/docker-ssd/docker/compose/pihole`
-  - NOMAD backup live at `/opt/pihole-nomad`
+- [x] Deploy Pi-hole HA on PD + N.O.M.A.D. with VIP `10.5.30.53` — completed 2026-05-15; historical design later superseded by the Technitium trio. As of 2026-05-27 the PD primary runtime at `/mnt/docker-ssd/docker/compose/pihole` has been retired, while the legacy VIP still survives from NOMAD's leftover stack at `/opt/pihole-nomad`; see docs/planning/DEPLOY_PIHOLE.md
+  - PD primary retired 2026-05-27 after local resolver cutover to Technitium (`10.5.30.8/.9/.10` + `9.9.9.9`)
+  - NOMAD legacy survivor still live at `/opt/pihole-nomad`
   - RPi4 remains optional future BACKUP2 work if you want a third node later
 - [x] Deploy Kima-Hub — completed 2026-05-06; docs/planning/DEPLOY_KIMA_HUB.md now serves as deployment/repair reference
 - [ ] Set up off-site backup for vital data (appdata, databases, config repo, photos)