[TheFabFab]

Six additive changes DocuMentor's project discussions rely on (documentor/FORK.md has a row for each). A client that sends none of the new fields gets today's behaviour, so the released image runs the currently pinned DocuMentor unchanged.

• schema/v1/session.ts: a user message's info carries author?: {id, name} and answerable?: boolean.
• session/prompt.ts + session/message-v2.ts: an unanswerable message is context, never the message a turn answers; prompt with answerable: false stores and returns; a session with nothing answerable resumes without a step. In a session whose metadata is { documentor: { kind: "discussion" } }, the model input prefixes each authored human message with Name: .
• session/compaction.ts: in a discussion, the summary input prefixes each authored message with Name: ; prune and the retained-tail count skip side remarks (answerable: false).
• acp/service.ts: _meta.documentor = { author, answerable, noReply, system, partMetadata } on session/prompt, _meta.documentor.metadata on session/new; a stored-only prompt answers end_turn without waiting for an idle event that never comes.
• acp/event.ts: replayed user_message_chunk carries _meta.opencode with the author and the part metadata.
• sdk/js/src/v2/gen: regenerated; session.prompt and session.promptAsync forward author and answerable.

Verified locally: the documentor: cases in the touched test files (event, service-session, prompt, message-v2, compaction; all pass in full), bun turbo typecheck, check:generated, and binary-smoke.sh on a --single build.

Design: TheFabFab/KPG docs/superpowers/specs/2026-10-12-project-discussions-design.md.

🤖 Generated with Claude Code

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[github-actions]

Hey! Your PR title Project discussions: author and answerable on user messages, attributed model input, ACP meta doesn't follow conventional commit format.

Please update it to start with one of:

• feat: or feat(scope): new feature
• fix: or fix(scope): bug fix
• docs: or docs(scope): documentation changes
• chore: or chore(scope): maintenance tasks
• refactor: or refactor(scope): code refactoring
• test: or test(scope): adding or updating tests

Where scope is the package name (e.g., app, desktop, opencode).

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