Address review: `agentType` was a Claude-Code concept (`subagent_type`) that
does not fit our own subagent seam — nothing in the harness interprets it, and
its only consumer was the CC-dialect hook bridge. Rather than let a foreign
concept sit on the core seam, remove it:
- `SubagentStartRequest`, `SubagentRunInfo`, `SubagentRunEndInfo`: drop the
`agentType` field; the `subagent/start`/`subagent/end` payloads now carry
`provider`/`id` (+ end `stopReason`/`lastAssistantMessage`) only.
- `dsh-tool-subagent`: drop `Config.agentType` and its request plumbing.
- Tests: keep the lastAssistantMessage / clone-containment / reject-path
coverage (rewritten to not assert agentType); delete the two tool-subagent
tests that only exercised agentType forwarding (dead behavior).
- Docs: retitle + rewrite the subagent-observe-enrich RFC to the one shipped
enrichment (lastAssistantMessage), with a note on why agentType was dropped;
update rfc/README index title, both subagent READMEs, and the
core-data-structures/subagent.md type-equiv block + prose; regenerate catalog.
The CC bridge (PR-F) will feed Claude Code's own default matcher value
"general-purpose" for its SubagentStart/Stop agent_type matcher instead.
Tianyi Cui
84f3019310