[HZ 2col] inventory test

Flat 2-column grid (invisible links; left = front+app, right = data/egress/idle):

flowchart TB
  web["`**web**
OpenResty (nginx + Lua)
_reverse proxy · rate/conn + bandwidth limits_
_serves /-/u/* uploads · publishes :80 :443_`"]:::front
  cache["`**cache**
Redis 8.6.1 :6379
_presence · watchbar · login secrets_
_link-preview cache · auto-SSL storage_`"]:::front
  app["`**app**
JVM Java 11 · Play (Scala)
_talkyard-server :9000_
_React SSR in-JVM (Nashorn)_`"]:::appt
  rdb["`**rdb**
PostgreSQL 18.3 :5432
_all forum data_`"]:::appt
  search["`**search**
Elasticsearch 9.3.1 :9200
_full-text index_`"]:::appt
  egressp["`**egressp**
Smokescreen :4750
_SSRF-filtering egress proxy_`"]:::egr
  rendr["`**rendr**
debian-slim
_placeholder — no traffic today_`"]:::idle
  backup["`**backup**
pg_dumpall + gpg
_profile-only · on-demand_`"]:::idle
  web ~~~ cache ~~~ app ~~~ rdb
  search ~~~ egressp ~~~ rendr ~~~ backup
  web ~~~ search
  classDef front fill:#dcfce7,stroke:#16a34a,color:#14532d
  classDef appt fill:#e0e7ff,stroke:#6366f1,color:#312e81
  classDef egr fill:#fee2e2,stroke:#dc2626,color:#7f1d1d
  classDef idle fill:#f3f4f6,stroke:#9ca3af,color:#4b5563,stroke-dasharray:5 5

End.