ROADMAP-26 — P3 — Configurable retention for runs/steps #118

Series: ROADMAP — filed from the 2026-10-27 whole-project assessment · Backlog task: M17-T05 · Priority: P3 · Effort: small/medium

Problem

Redis sessions expire (SESSION_TTL_S) but PostgreSQL never does: runs and steps (including steps.result JSON) persist forever. With no retention policy, the audit virtue becomes unbounded storage growth and eventual steps-table pressure on every dashboard query.

Acceptance criteria

• STEPS_RETENTION_DAYS (and optionally RUNS_RETENTION_DAYS) settings — default keeps current behaviour (no deletion) until enabled
• A documented cleanup path: app-side scheduled task, or pg_cron/partitioning recipe in docs/DEPLOY.md (pick one primary, document the other)
• Index support for the deletion predicate (see ROADMAP-08's created_at index)
• Test: retention task deletes only eligible rows

Suggested branch / commit

chore/steps-retention · chore(db): configurable retention for runs and steps