Preserve unknown review counts when pagination fields are missing #485

🤖 Generated by the Agentic Engineer

Problem

An empty terminal review-thread page can omit a requested cursor field and still produce a successful zero count. That incomplete read is indistinguishable from a complete clean observation.

Proposal

Require the complete requested pagination shape, including a null cursor for an empty terminal page.

Acceptance criteria

Missing pagination fields produce QUERY-UNKNOWN with no clean count; a complete empty terminal page still reports zero and valid multi-page observations remain supported.

Reproduced offline against freshly fetched main using synthetic fixtures. No inspected source was executed and no provider experiment was launched. Size: S.

Part of #51.