#8708 chore(table): remove unused table-update background task

Summary

• Remove the table-update Trigger.dev task and its runner (lib/table/update-runner.ts) — nothing has dispatched it since the Copilot bulk-rows use case that triggered it was deleted in #8549; bulk updates by filter run inline via updateRowsByFilter
• Remove updatePageByIds / PagePatch from lib/table/rows/ordering.ts (only the runner used them), the runner's unit test, and the integration block that exercised the background path
• Drop stale comments that pointed at the runner
• TableJobType keeps 'update' so historic table_jobs rows still parse; no schema change

Type of Change

• Chore

Testing

• Confirmed no static or dynamically built table-update dispatch and no remaining creator of update table jobs
• bun run lint, bun run type-check, bun run check:audits, bun run docs-manifest:check, block-registry check — green
• Root bun run test: all green except 3 unrelated heavy tests that timed out under machine load; each passes when re-run on its own

Checklist

• Code follows project style guidelines
• Self-reviewed my changes
• Tests added/updated and passing (new tests pass the test-audit authoring gate)
• No new warnings introduced
• I confirm that I have read and agree to the terms outlined in the Contributor License Agreement (CLA)