Docs-as-code: full deploy configs, compose stacks, and DR guide

- Add root README and docs/ (architecture, hosts, disaster-recovery, operations)
- Add compose/ for superset, forgejo, lam, cadvisor; unified deploy compose
- Add scripts/deploy (deploy-atc-docker01.sh, container inventory export)
- Add inventory/containers-atc-docker01.json snapshot
- Add config READMEs for kafka and airflow; .env.example; expand .gitignore
- Sync atclab helper scripts; update homepage/superset compose with env support

scripts/atclab/r

@@ -0,0 +1,23 @@
+#!/usr/bin/bash
+
+DEL=""
+
+deletehost() {
+  local host ip
+  host=$(echo $1 | awk -F@ '{print $NF}')
+  ip=$(host $host | awk '/has address/ {print $NF}' | head -1)
+  ssh-keygen -R $host
+  test -n "$ip" && ssh-keygen -R $ip
+}
+
+while getopts ":dh" OPT; do
+  case "$OPT" in
+    d) DEL=Y ;;
+ \?|h) usage >&2 ; exit 0 ;;
+  esac
+done
+shift $(expr $OPTIND - 1)
+
+test -n "$DEL" && deletehost $@
+
+ssh root@${1:-none}