`_tick` skipped `drawing`: the wait for the draw block lived only inside the
`_close_and_draw` call that entered it, so any exception (a locked database writing an
audit row, a malformed header) or a restart left the round in `drawing` for ever with the
pool inside and no new round able to open.
Since B-73 everything the draw needs is committed on entering `drawing` (encrypted secret,
ordered list with `draw_position`, `participants_hash`, `draw_height`, `draw_confirmations`),
so `_tick` now calls `_complete_draw` for a round in `drawing`. `_complete_draw` rereads that
state, is idempotent (a round no longer `drawing`, or with a winner, is left alone; the
winner write is re-checked under BEGIN IMMEDIATE) and runs inside the single scheduler loop,
so the inline call from `_close_and_draw` and the tick can never run concurrently.
Tests (test_draw_proof.py): an exception in the quorum query, then a tick, completes with the
same height, list, fingerprint and the winner the public proof recomputes; a brand-new
scheduler (restart) resumes and a second tick draws and triggers nothing again; a failure in
the very transaction that stores the winner leaves no winner and no revealed secret, and the
next tick completes. Mutation-checked: without the `_tick` branch all three fail.
Docs: the B-81 `*Stato:*`/`*Oggi:*` lines are gone (RND-01, RND-15, RND-36, ARC-27, OPS-09,
ADR-12, ADR-25), OPS-13 no longer prescribes the manual `closing` workaround, LIM-01 is
struck, storico-bug.md and BUGS.md updated. No existing test changed.
Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>
davideandClaude Sonnet 5.5
473d541ab5