Gap when no gap is needed

Sometimes a gap is shown when the gap only represents a single number. In this case, the gap could show the number instead.

For example:

This could be rendered as:

[1, ..., 12, 13, 14, 15, 16]

Start by locating the pagination-array entry point and reproduce the example where a gap represents only one number. Verify that this singleton gap is rendered as the number itself, while multi-number gaps still use the existing gap marker and the shown example produces the requested array.

Written by the indexing model from the issue text.