fix: telegraf containers names + openremote pg image + session snapshot 2026-05-25

- telegraf.conf: fix Mosquitto/BunkerM container names (hyphens not underscores)
- tegraf.conf: comment out BunkerM consumer (auth fails, simulator not sending)
- openremote/docker-compose.yml: switch PG image to timescaledb-ha:pg15 (fixes timescaledb_toolkit crash)
- Add session_resume + architecture snapshot 2026-05-25
- Update TODO.md with current status

docker-compose.the-things-stack.yml

@@ -11,6 +11,7 @@ version: "3.8"
 
 services:
   tts-postgres:
+    container_name: smart-city-tts-postgres
     image: postgres:14
     restart: unless-stopped
     environment:
@@ -22,6 +23,7 @@ services:
     networks:
       - smartcity-shared
   tts-redis:
+    container_name: smart-city-tts-redis
     image: redis:7
     command: redis-server --appendonly yes
     restart: unless-stopped
@@ -30,6 +32,7 @@ services:
     networks:
       - smartcity-shared
   tts-stack:
+    container_name: smart-city-tts-stack
     image: thethingsnetwork/lorawan-stack:latest
     entrypoint: ttn-lw-stack -c /config/ttn-lw-stack-docker.yml
     command: start