chore: add ImageViewer Navigation Index label

[bluelovers]

Description

• a simple description of what you're trying to accomplish
• a summary of changes in code
• which issues it fixes, if any

Screenshots/videos:

Checklist:

• I have read contributing wiki page
• I have performed a self-review of my own code
• My code follows the style guidelines
• My code passes tests

[w-e-w]

I don't like it
it gets into the way of portrait images

if this is implemented I think it should show only on Hover and

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it's been off center also really bothers me

there's also no point of showing the text when there's only one image
in my opinion, it's also isn't that much useful unless you're dealing with lots of images

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even if this PR is straightforward that mostly things can be conveyed through a screenshot
you should still give a simple description
how much time would it take one minute?

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and it's not a good idea to use images that can be considered NSFW for work or screenshots