Todo/Tasks list tool #21

[Olga Lavrichenko (OLavrik)]

What: a durable, per-worktree backlog (the right-panel Todo tab) the user curates and the pi agent executes.

How it works:

• User curates — add items, set priority (click chip: low→normal→high, default normal), remove.
• Run (▶) opens a chat, injects a prompt from the item, and binds it to that session. Status is agent-owned (no manual toggle): the agent flips pending→in_progress→done, and the panel shows it live.

How it's built (mirrors spec-graph, 4 layers):

1. packages/pi-todos — pi extension: pi-free TodoStore (.thinkrail/todos.json) + five todo_* tools + skill + always-on rule.
2. contracts — TodoItem + todo.list/add/update/remove/bind routes (PROTOCOL_VERSION 2).
3. server/todos — value-imports pi-todos/core, maps routes to the store; todo.bind writes the run→chat sessionId host-side only (agent owns status, host owns binding).
4. TodoPanel — reads/curates over the wire; live status by piggybacking the pi.event stream (refetch on tool-end / turn-settle); Run reuses chat-kickoff, Open-chat reuses the reopen flow.

Verified: unit (core+tools), e2e no-agent (curate/reprioritize/refresh), e2e AGENT, Inc. (@agent) (Run→live done→reopen chat).