0613 — column naming rules

Context

The [0611] table review’s column audit, run over the live tbls snapshot (just schema-diagram), found the same fact spelled differently across tables: lease expiry as until / expires_at / lease_until, an attempt’s timestamp as attempt_at / attempted_at, schedule instants as _time, and pattern meaning the derived POSIX regex in binding but the declared NATS-style form in binding_log. The user’s opaque document is payload on messages but data on cron jobs, though the cron job’s data becomes the produced job request.

Decision

The rules:

• Instants end _at: past events as past participles (created_at, declared_at, attempted_at), expiry always expires_at, and a lower-bound gate ends _after (can_run_after stays — “any time after T” is information _at loses).
• A fact about the row itself is bare; a fact about an attached concept carries that concept’s prefix (claim_lease.token vs exception_queue.lease_token); last_ marks latest-of-many.
• Singular = ordinal (attempt), plural = running count (attempts, reclaims) — the logging registry’s rule, extended to columns.
• Durations are BIGINT nanoseconds ending _ns.
• The user’s opaque document is payload everywhere.

The renames: binding_log.attempt_at→attempted_at, lease.until→expires_at, delivery.lease_until→ lease_expires_at, cron_job’s next/last_scheduled_time→ next/last_scheduled_at (moving to cron_job_cursor per [0611]), binding.display→pattern with binding.pattern→pattern_regex (so pattern means the declared form everywhere), and cron_job.data→payload — a public-surface change: cron.CronJob.Data and cron.JobRequest.Data become Payload, wire tag data→payload, plus the declare path’s field. JobRequest.ScheduledTime→ScheduledAt (wire scheduled_at) rides the instants rule. alert.Alert.Data stays — the alert message’s own field, an open candidate, not cron payload plumbing.

Consequences

• Unchanged and deliberate: head_id, the cursor’s role-named message ids, error/last_error, token, can_run_after.
• The _at/_after and _ns rules are machine-checkable — a tools/conventions walk over the schema (or tbls schema.json) should enforce them so drift cannot recur.
• Ships with the [0611]/[0612] rename sweep; the cron payload rename sweeps docs, examples, and labs with it (grep labs for ->>'data').