fix: address codex review round 2

- Wire the control service and send_message tool into every shipped
  composition with a resumable provider and background enabled
  (headless-agent, tui-agent, and the SDK helper's subagent feature
  base resources); jsonrpc-agent disables background and is unchanged.
- Resolve the send_message availability check in the CALLER's tool
  scope so a restriction that removes the follow-up tool from one
  agent also blocks that agent's continuable start.
- Control-service disposal now cancels live activations and awaits
  producer settlement instead of stranding them: TaskService keeps
  producer Tasks across a reload, so the disposing service aborts each
  activation-owned controller, resolves its terminal gate (the
  effect-scoped onTaskDone listener is already gone), and awaits done.
  A new test kills a mid-start activation through HMR disposal.

apps/cli/package.json

@@ -101,6 +101,7 @@
     "@deepseek-ai/dsh-storage-domain": "workspace:^",
     "@deepseek-ai/dsh-storage-json": "workspace:^",
     "@deepseek-ai/dsh-subagent": "workspace:^",
+    "@deepseek-ai/dsh-subagent-control": "workspace:^",
     "@deepseek-ai/dsh-subagent-fork": "workspace:^",
     "@deepseek-ai/dsh-subagent-spawn": "workspace:^",
     "@deepseek-ai/dsh-subprocess-local": "workspace:^",
@@ -120,6 +121,7 @@
     "@deepseek-ai/dsh-tool-skill": "workspace:^",
     "@deepseek-ai/dsh-tool-str-replace-editor": "workspace:^",
     "@deepseek-ai/dsh-tool-subagent": "workspace:^",
+    "@deepseek-ai/dsh-tool-subagent-control": "workspace:^",
     "@deepseek-ai/dsh-tool-tasks": "workspace:^",
     "@deepseek-ai/dsh-tool-todo": "workspace:^",
     "@deepseek-ai/dsh-tool-web": "workspace:^",