Tasks

1. Spec

• 1.1 Add polyfill-runtime requirements for source-partition coverage honesty and partition-aware cursors.
• 1.2 Validate the OpenSpec change strictly.

2. Slack Connector

• 2.1 Add current archive channel inventory extraction.
• 2.2 Compare prior observed channels with current archive channels.
• 2.3 Emit bounded SKIP_RESULT diagnostics for missing previously observed channels.
• 2.4 Persist messages.channel_last_ts and messages.observed_channel_ids.
• 2.5 Use per-channel message high-water thresholds when iterating MESSAGE rows.
• 2.6 Add a dry-run-by-default repair script to seed Slack message partition state from retained records.
• 2.7 Add isolated scoped Slack archives for targeted channel backfills.
• 2.8 Add collector-runner --resources support so backfills can use the normal ingest path.
• 2.9 Add owner/ref run-route resources support so targeted backfills can be triggered through the normal audited run path.

3. Tests

• 3.1 Cover missing prior Slack channel diagnostics.
• 3.2 Cover clean inventory with no diagnostic.
• 3.3 Cover per-channel cursor emission and legacy fallback.
• 3.4 Cover repair-script merge semantics and backup-table naming.
• 3.5 Cover scoped Slack archive backfill behavior.
• 3.6 Cover collector-runner START resources.
• 3.7 Cover controller and run-route propagation of scoped resources.

4. Validation

• 4.1 Run focused Slack connector tests.
• 4.2 Run repair-script tests.
• 4.3 Run package typecheck or equivalent focused TypeScript validation.
• 4.4 Summarize live-data implication and repair/deploy follow-up.