fix(hub): 对齐 ADR-0018 agent 执行面边界

runner.ts: 启用 SDK 内置沙箱(bubblewrap/seatbelt),写入限制在 workspace,
denyRead 敏感路径,failIfUnavailable 硬拒非沙箱运行。bypassPermissions 保留
(headless 无交互),沙箱是硬边界而非权限提示层。

install_service.sh: 默认 service user 从 root 改为 cph-hub;env 模板修正
OPENROUTER_API_KEY → ANTHROPIC_AUTH_TOKEN/ANTHROPIC_BASE_URL/ANTHROPIC_API_KEY
(与 server.ts 实际读取一致);补 __BASE_DIR__ sed 替换。

cph-hub.service: AssertPathExists=/usr/bin/bwrap 强制沙箱依赖;NoNewPrivileges。
不加 ProtectSystem/ProtectHome(会破坏 cph render-cache 与 bwrap user-namespace)。

trigger.ts: 权限闸门去掉 if (senderOpenId !== '') 短路——缺 open_id 一律
fail-closed 拒绝,不再静默跳过;role gate 同步去掉冗余守卫(已由上游保证)。
顺手把 JSON.parse(msg.content) 的 inline cast 换成 Zod schema parse
(FileMessageContentSchema / TextMessageContentSchema)。

ADR-0018: 状态改为 Accepted+implemented,机制段写定 SDK 沙箱,网络决定为开放,
Open Questions 更新。

hub/deploy/cph-hub.service

@@ -16,6 +16,11 @@ RestartSec=5
 # Graceful shutdown: lark ws close + in-flight runs.
 KillSignal=SIGTERM
 TimeoutStopSec=30
-
-[Install]
-WantedBy=multi-user.target
+# ADR-0018: the agent sandbox (bubblewrap) must be available on the host —
+# failIfUnavailable makes the Hub refuse to run unsandboxed. Install bwrap.
+AssertPathExists=/usr/bin/bwrap
+# Hardening: no new privileges. ProtectSystem/ProtectHome are NOT set here —
+# they would break cph's render-cache extraction (~/.cache/cph/) and the
+# bwrap user-namespace setup. The OS-level sandbox (ADR-0018) is the hard
+# boundary; systemd hardening is kept minimal to avoid interfering with it.
+NoNewPrivileges=true