rdmsm4x — Tyrell Builds 51 + 52: hub I/O fixes (tyrell-64)

[2026-09-28 00:25 EDT → 02:25 EDT · rdmsm4x · claude@rdmsm4x/tyrell-64, Opus 5.5 lead; Opus workers and reviewers]

• Build 51 on 6/6 (v0.2.0-build51): bus index incremental passes (ISSUE-20260928-01). Hub mail ops fell from 2,632 to 7–8 per 6 s.
• Build 52 on 6/6 (v0.2.0-build52): a per-host files summary replaces the full-table rescans the 15 s fleet loop ran over about 10M rows (ISSUE-20260928-02). It went through two Opus review rounds that caught wrong counts before shipping. Hub pread on tyrell.db fell from 391,389 to about 3,700 per 4 s. The backfill held the write lock for 4.95 s, which is tracked in ISSUE-20260928-04.
• Remaining hub load at 02:17 was mediaanalysisd plus 1Password, not Tyrell.
• Replaced copies went to Trash, keeping one rollback per host. TCC was unchanged and there were no prompts.