v9.1.0

Brain Framework 9.1 prepares team deployments. The brain format is unchanged: existing version 3 brains need no conversion.

Added

• bf init --no-collect registers a shared brain for search without collection trust, and init accepts a fresh clone of an empty repository.
• A team brains guide: distinctive names, joining, CI collection with preserved run state, allowlisted memories/ publication, required review of sensor code, and data retention.
• A documented compatibility policy: the brain, bf.yaml and queries.yaml formats change only in a major release, with manual upgrade steps.

Fixed

• bf init anchors .gitignore patterns to the brain root, so actions/*/inputs/ stay versioned and a teammate's clone validates like the author's copy. Existing brains that copied the old patterns should prefix inputs/, logs/, memories/, originals/ and .bf/ with /.
• bf init names a brain after its directory instead of knowledge, avoiding registry name collisions between personal and team brains, and explains how to resolve a taken name.
• Unsupported platforms fail with a clear message instead of an import traceback.

Changed

• Call executable collectors sensors in command help, documentation and the bf-maintain skill; record refs, --source, health sources and OKF sources keep their provenance names. search --source now has help text.