Production docker tasks: --docker-runtime runsc in autoscaler unit

One-off worker verification passed before this flip (2026-10-26):
production-shaped docker task (apparmor=docker-codex, pids-limit 512,
tenant isolation, egress proxy 8888, --docker-runtime runsc) completed
in 60s with gpt-6.1-sol, worktree quadruple + proof verified, template
and tenant repo copies clean. README now states the production state.

deploy/autoscaler/codex-autoscaler.service

@@ -14,7 +14,7 @@ EnvironmentFile=/etc/codex-app-server/env
 # scaler 会按实例强制追加；--db 只给 scaler，scaler 会补给 worker。
 # 注意：启用 autoscaler 后必须停掉静态 codex-cloud-worker，
 # 否则两边同时派任务（scaler 只管理 autoscale-* 实例）。
-ExecStart=/usr/bin/python3 -m cloud.autoscaler --db /var/lib/codex-app-server/control.db --interval 30 --min-workers 1 --max-workers 2 --per-worker-capacity 2 --scale-down-after 3 --drain-timeout 60 --state-file /var/lib/codex-app-server/autoscaler-state.json --log-dir /var/lib/codex-app-server/autoscaler-logs -- --interval 10 --config /opt/codex-app-server/host-config-docker.json --executor docker --docker-image codex-app-server:latest --docker-user 1003:1004 --docker-cpus 2 --docker-memory 2g --docker-extra-mounts /opt/codex-app-server/work:/app/work,/var/lib/codex-app-server/codex-home:/var/lib/codex-app-server/codex-home,/var/lib/codex-app-server/repos:/var/lib/codex-app-server/repos,/var/lib/codex-app-server/test-repo:/var/lib/codex-app-server/test-repo --repos-dir /var/lib/codex-app-server/repos --tenant-isolation --tenants-root /var/lib/codex-app-server/tenants --tenant-template-home /var/lib/codex-app-server/codex-home --tenant-template-repo /var/lib/codex-app-server/test-repo --docker-security-opt apparmor=docker-codex --docker-pids-limit 512 --egress-proxy-port 8888
+ExecStart=/usr/bin/python3 -m cloud.autoscaler --db /var/lib/codex-app-server/control.db --interval 30 --min-workers 1 --max-workers 2 --per-worker-capacity 2 --scale-down-after 3 --drain-timeout 60 --state-file /var/lib/codex-app-server/autoscaler-state.json --log-dir /var/lib/codex-app-server/autoscaler-logs -- --interval 10 --config /opt/codex-app-server/host-config-docker.json --executor docker --docker-image codex-app-server:latest --docker-user 1003:1004 --docker-cpus 2 --docker-memory 2g --docker-extra-mounts /opt/codex-app-server/work:/app/work,/var/lib/codex-app-server/codex-home:/var/lib/codex-app-server/codex-home,/var/lib/codex-app-server/repos:/var/lib/codex-app-server/repos,/var/lib/codex-app-server/test-repo:/var/lib/codex-app-server/test-repo --repos-dir /var/lib/codex-app-server/repos --tenant-isolation --tenants-root /var/lib/codex-app-server/tenants --tenant-template-home /var/lib/codex-app-server/codex-home --tenant-template-repo /var/lib/codex-app-server/test-repo --docker-security-opt apparmor=docker-codex --docker-pids-limit 512 --egress-proxy-port 8888 --docker-runtime runsc
 Restart=on-failure
 RestartSec=10
 # 停 scaler 时要等它把 worker 优雅排空（drain 60 秒 + 缓冲），