Add this PhotoViewer Sample to the main readme list

[iurycarlos]

• add a readme with more info for this sample at the same time on in another PR please ? cf. https://github.com/unoplatform/Uno.Samples/pull/650#issuecomment-2037851011

  @iurycarlos can you add this sample to the main readme list + add a readme with more info for this sample at the same time on in another PR please ? cf. https://github.com/unoplatform/Uno.Samples/pull/650#issuecomment-2037851011

Originally posted by @agneszitte in https://github.com/unoplatform/Uno.Samples/pull/655#pullrequestreview-1983312454

[agneszitte]

@iurycarlos just fyi but based on when you will do your changes for this issue, I have this in progress PR that should be merged soon and it was to let you know that the main samples list will be moved from the main readme so we can use it for the uno documentation website.