21.2.1 (2026-09-02) Bug Fixes pi-subagents: tear the agent widget down on session shutdown (a9a7a63), closes #849 Documentation pi-permission-system: record the fact-shaping inheritance rule (ADR 0012) (dbdd9f1) Miscellaneous Chores upgrade lint tooling and pin rumdl below the MD013 reflow regression (0ee1ad8), closes #866 upgrade fallow to 3.22.0 (1b2a562), closes #866