0743 — Maintenance completion tracking and startup delay are deferred

Context

Review of 0742 identified successful-pass tracking and randomized initial vacuum delay as extra features. The user requested their removal and separate Later items for consideration.

Decision

Supersede 0742 only in completion tracking and initial scheduling; retain its maintenance configuration and operational model.

Remove RecordSuccess and InitialDelay from the tick runner. The first tick is immediate. Success resets the failure streak only after recovery, using the existing update without appending completion history. Remove the added completion column, index, snapshot field, query, and feature-specific test. Keep the existing jitter between subsequent passes and failure backoff.

Consequences

Status reports operational targets, live claims, and failures, without a last-success timestamp. This change requires no completion-history schema addition. Both features remain separate Later considerations whose benefit and cost must be evaluated before implementation.