feat(subagent): add Claude Code provider

docs/core-data-structures/subagent.md

@@ -4,7 +4,7 @@ English | [中文](subagent.zh.md)
 
 The subagent seam — an agent delegating work to a child agent. Like [bash](bash.md) it is **one optional capability**, not part of the agent-loop spine, so its vocabulary lives here rather than in [core.md](core.md). But it differs from every other seam on one axis: **multiple provider implementations coexist** in one context, registered by name (`ctx.subagents`), where bash allows only one executor. The registry shape mirrors the [LLM adapter registry](llm-streaming.md), not the single-service bash executor.
 
-Interface: [dsh-subagent](../../packages/subagent/subagent) (`ctx.subagents` + the vocabulary below). Implementations are sibling packages (`dsh-subagent-spawn`, `-fork`, `-acp`, `-codex`, `-dsh-sdk`); the model-facing consumers are [dsh-tool-subagent](../../packages/subagent/tool-subagent) (per-provider delegation), [dsh-tool-subagent-control](../../packages/subagent/tool-subagent-control) (the optional global `send_message` and `list_agents` controls), and [dsh-tool-subagent-report](../../packages/subagent/tool-subagent-report) (the optional child-scoped `report` return channel). The same `ctx.subagents` service owns continuable-child orchestration through an internal activation manager and read-only direct-child discovery through optional session query. The rationale lives in [the subagent Agent Note](../../.agents/notes/implemented/feature/2026-06-21-subagent-capability-seam.md), [the continuable subagents Agent Note](../../.agents/notes/implemented/feature/2026-07-28-continuable-subagent-conversations.md), [the report-tool Agent Note](../../.agents/notes/implemented/feature/2026-07-30-continuable-subagent-report-tool.md), [the durable catalog Agent Note](../../.agents/notes/implemented/feature/2026-07-22-durable-subagent-catalog-and-list-agents.md), and [the merged-service Agent Note](../../.agents/notes/implemented/simplification/2026-07-26-merge-subagent-control-service.md).
+Interface: [dsh-subagent](../../packages/subagent/subagent) (`ctx.subagents` + the vocabulary below). Implementations are sibling packages (`dsh-subagent-spawn`, `-fork`, `-acp`, `-codex`, `-claude-code`, `-dsh-sdk`); the model-facing consumers are [dsh-tool-subagent](../../packages/subagent/tool-subagent) (per-provider delegation), [dsh-tool-subagent-control](../../packages/subagent/tool-subagent-control) (the optional global `send_message` and `list_agents` controls), and [dsh-tool-subagent-report](../../packages/subagent/tool-subagent-report) (the optional child-scoped `report` return channel). The same `ctx.subagents` service owns continuable-child orchestration through an internal activation manager and read-only direct-child discovery through optional session query. Product-provider rationale lives in [the Codex and Claude Code Agent Note](../../.agents/notes/implemented/feature/2026-08-04-claude-code-and-codex-subagent-backends.md); common-seam rationale lives in [the subagent Agent Note](../../.agents/notes/implemented/feature/2026-06-21-subagent-capability-seam.md), [the continuable subagents Agent Note](../../.agents/notes/implemented/feature/2026-07-28-continuable-subagent-conversations.md), [the report-tool Agent Note](../../.agents/notes/implemented/feature/2026-07-30-continuable-subagent-report-tool.md), [the durable catalog Agent Note](../../.agents/notes/implemented/feature/2026-07-22-durable-subagent-catalog-and-list-agents.md), and [the merged-service Agent Note](../../.agents/notes/implemented/simplification/2026-07-26-merge-subagent-control-service.md).
 
 Sources: [`packages/subagent/subagent/src/types.ts`](../../packages/subagent/subagent/src/types.ts), [`packages/subagent/subagent/src/index.ts`](../../packages/subagent/subagent/src/index.ts), and [`packages/subagent/subagent/src/continuation.ts`](../../packages/subagent/subagent/src/continuation.ts)