Round 4 review (PR #910), no blockers:
- poll(): a 2xx body with no `status` now fails fast (logged) instead of being
treated as perpetually pending until the deadline; defensive page index
(`p.get("index", i)`) so a malformed page degrades rather than KeyError-ing.
- Document on poll() that job_id is namespaced (embeds "/") so the gateway route
must be a path-capture param (GET /v1/ocr/batch/{job_id:path}).
- Drop the vestigial `status` + `updated_at` columns from batch_ocr_jobs: a row
only ever exists while pending (terminal jobs are deleted) and the live status
comes from a fresh poll, so a stored mirror was permanently "pending" /
redundant with submitted_at. Simplifies the migration, store, and dataclass.
- Tests: submit() ValueError on missing job_id; poll() missing-status → failed.
1653 unit tests pass; ruff + ty green.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
