Phase D: Staleness and liveness automation

[jlucus]

Part of milestone v2.1.0 — Community Data Pipeline. Full plan: docs/02-project-scope/DATA_PIPELINE_PLAN.md.

Scope

Automation that demotes trust instead of humans re-checking everything: this is where automated gathering genuinely reduces verification load.

Acceptance criteria

• Venue missing from OSM on two consecutive runs → demote to "Needs recheck"
• Hours-feed change since last observation → flag and re-score
• Cheap HTTP liveness check on venue websites in the daily run
• Field checks older than 90 days auto-demote (matches the published verification table)
• Demotions visible in the site badges without manual edits