[Feature] Improve the inspecting results section for adding a new atlas

The inspecting results for packaging a new atlas could be improved https://github.com/brainglobe/brainglobe.github.io/blob/be3c21cf516b0c2eac41fc9032e78306e55907c2/docs/source/documentation/brainglobe-atlasapi/adding-a-new-atlas.md?plain=1#L130-L162.

@PolarBean, has lots of experience in packaging and verifying the new V3 atlases so I'll let him take the lead! Perhaps we can use neuroglancer to render the atlas pointing to a local set of files.

Start with docs/source/documentation/brainglobe-atlasapi/adding-a-new-atlas.md, especially lines 130-162, and review how inspecting results are described for packaging a new atlas. Clarify and update that section so the packaging and verification results are adequately documented, including whether the proposed local Neuroglancer rendering workflow is needed.

Written by the indexing model from the issue text.