bootstrap-corpus fixture

A tiny, hermetic, 100% synthetic brain corpus used by the agent-bootstrap end-to-end tests. It is curated and re-authored (not copied wholesale) from the public gbrain-evals synthetic corpora — eval/data/synthetic-v1 (interlinked markdown pages with frontmatter, [[wikilinks]], and ## Timeline sections), eval/data/world-v1 (compiled-truth entity JSON), and eval/precisionmembench/fixtures (preference/belief objects with visibility + confidence). Every name here is an obvious placeholder (alice-example, ridge-platform, summit-robotics, vector-co, …); no real person, company, or fund appears, per the repo privacy iron rule.

Contents:

• pages/*.md — 12 interlinked pages (people, companies, concepts, meetings) with YAML frontmatter and [[wikilinks]]. Filenames flatten the slug: companies__ridge-platform.md loads as slug companies/ridge-platform. Four pages carry a ## Timeline section.
• beliefs.json — belief/fact objects { text, entity_slug, visibility, confidence }, a mix of world and private, so a visibility-fence recall test can assert the private ones are never surfaced.
• queries.json — gold recall cases { id, kind, query, expect_slug?, expect_substring?, must_not_substring? }, each with a deterministic answer given the pages/beliefs above.

The loader in test/helpers/bootstrap-corpus.ts reads these files and writes the pages through the real put_page operation handler (so auto-link, chunking, and search-vector fire) and the beliefs through engine.insertFact (honoring each belief's visibility). loadCorpusQueries() returns the parsed gold cases. Consume the loader read-only; do not mutate the fixtures from a test.