Give the root's Chat and Planner reach into child documents

[MaggieAppleton]

What changes

There is now one Chat per root document. Child documents no longer have their own Chat: the root's Chat applies to every child, and the Planner can read and edit children from it.

• Focus: when a child is open, a message to the Planner from the root's Chat carries that child as focus. The server checks the child belongs to the root, and the Planner's prompt names it.
• New Planner tools: list_children, read_child, edit_child and anchor_child.
  • They share their edit and anchor code with edit_plan and anchor_plan, including dialect validation and persistence before publication.
  • Every call rechecks the Planner owner's access (push or admin), the parentage, the repository and the archive state, under the child's own transition.
  • Background jobs never get them.
• Child comments: "Send to Chopin" in a child runs on the root's Chat with the child as focus, and the reply lands in the child's thread. A refusal or failure shows in the child, never as silence.
• MCP: invoke_planner on a child runs on the root's Chat in the same way, under the root's existing owner.
• Web: the root's composer sends the open child as focus. Clicking a child-comment notice in the root's transcript opens the child and its thread.

⚠️ Child Chat data is deleted at startup

As agreed (child chats were disposable), startup clears stored conversation data for child channels.

• It runs under the writer lease, in one transaction, and is idempotent.
• It never touches roots, documents, comment threads or question records.
• A child whose decision records cite its own chat messages is kept and logged, so it still loads. Its old conversation is never served.

flowchart LR
  subgraph Root document
    Chat[Root Chat] -->|chat:send focus = child| Planner
    Planner -->|list_children / read_child| Children
    Planner -->|edit_child / anchor_child| ChildDoc[Child document]
  end
  ChildComment[Comment in child: Send to Chopin] -->|routed with focus| Chat
  MCP[invoke_planner on child] -->|routed with focus| Chat
  Planner -->|reply_comment| ChildThread[Child comment thread]

Loading

Testing

• Unit tests:
  • storage children() and the child-conversation cleanup, as memory and Postgres contract tests (including a stale lease, diverged sidecars, archived children and children with no snapshot row)
  • checked child access
  • focus validation, including a busy queue draining
  • the child tools, authorization and error shielding
  • the tool boundary, including the Copilot adapter live check
  • comment and MCP routing, including room holds released only when the routed turn ends and a root closed mid-turn
  • web open-comment scoping
• New e2e/harness-children.e2e.ts, run with the fake Planner harness:
  • focus goes to edit_child, which lands in the child only
  • the child socket serves no Chat
  • Send to Chopin in a child, then opening it from the root's notice, with no false "no longer here"
  • switching from child A to child B
• bun run types, unit tests (4195 in the touched packages) and the design-contract check pass on the rebased head.

Initial bundle

To stay under the initial JS budget, DocumentRouteSwap moves out of hosted.tsx into a lazy document-route-view.tsx. It shows the same "Opening document…" fallback and preloads the workspace host. The parent-focus helper moves into the lazy host. Initial gzip drops by about 1 KB locally.

Design-contract review

Renewed after a data-flow review, with the maintainer's approval:

• document-workspace-host.tsx: the presentation gains a channel id and callbacks, not styles.
• document-workspace-host.tsx again: renewed after the focus helper moved in. No class or style changes.
• comment-layer.tsx and resolved-layer.tsx: the flagged expressions are unchanged, so only the hashes are new.

Slice 6 of the nested-documents work.

🤖 Generated with Claude Code