[MacHatter1]

Adds Lego to Threads & workflow, next to UltraGoal, because both spawn a worker thread per dependency-ready slice of work. UltraGoal keeps a standing objective and re-staffs slices with a second-model verifier, while Lego plans a single task up front and ends with one Master Builder that integrates it.

• Qualifies: package.json has a bb key (entries: server, app) and depends on @get-bb/plugin-sdk.
• Installs from the repo root: bb plugin install git:https://github.com/MacHatter1/bb-plugin-lego.git@v0.1.0. Tag v0.1.0, MIT.
• The entry states the costs and limits: every builder and the Master Builder is a separate agent session billed to your own providers, and they write directly into the planning thread's workspace with its permission mode. There are no message hooks and no external services.
• Also submitted to the bb Community marketplace: Add plugin entry: lego get-bb/marketplace#614.

[MGrin]

Merged, Tom. v0.1.0 (fea3329, seven commits) installs cleanly with bb's own steps on bb 0.46.1, plugin id lego.

The source matches the entry: eight builders at most (src/book.ts:26), builders and the Master Builder inherit the planning thread's permission mode (server.ts:375), one nudge before a bag fails, and no hooks or network calls.

#77 adds two things the neighbouring entries carry: Needs bb ≥ 0.46 from your engines field, and the five experimental_* SDK surfaces the UI uses.