Fix commits API incorrectly reporting hasNextPage: true when no more commits exist

Summary

The commits API incorrectly reports hasNextPage: true in the pagination response even when there are no more commits to fetch.

Context: !222424 (comment 3065323587)

Background

This was identified during the review of !222424 (merged) (Add cursor pagination to commit list). The frontend pagination relies on the hasNextPage value to determine whether to show/enable the "Next" button, but the backend is returning incorrect pagination metadata.

Expected Behavior

hasNextPage should return false when the current page contains the last commits in the list.

Actual Behavior

hasNextPage returns true even when there are no more commits, which can lead to users clicking "Next" and receiving an empty result set.

Acceptance Criteria

• hasNextPage correctly returns false when on the last page of commits
• Cursor-based pagination accurately reflects the remaining data

Related

• !222424 (merged) - Add cursor pagination to commit list (parent MR where this was identified)