Cleanup tag display for long lists of tags

[obulat]

Fixes

Fixes #2589 by @zackkrida

Description

This PR hides the tags beyond the third row and shows a "Show more tags" button if there are hidden tags.

I first tried simply hiding the tags setting the max height and using overflow-hidden. However, this way, you can navigate to the hidden tags using Tab. Even though those tags are not visible, they are focusable and are read by the screenreader.

That's why I added a function that detects the index of the tag that is the first on the 4th line of tags, and set the visibleTags value to the tags up to the "first on the 4th line". When the user clicks show more, the visibleTags is set to all of the tags, and when they click on hide tags, the visibleTags array only contains the first 3 lines.

For counting the rows of tags, I used offsetLeft, but had to make comparison operator (< or >) conditional to make it work with RTL (some of the first VR tests here for RTL are failures because I only used one comparison)

The expander button has a aria-expanded set to true or false based on whether the tags are all shown, or hidden.

Testing Instructions

Enable the additional_search_views on the /preferences page (note that this is only implemented for when this flag is on)
Go to an image result with many tags, such as [http://localhost:8443/image/7e138814-e774-45fb-91ee-7b728c174616?q=Titmouse](http://localhost:8443/image/7e138814-e774-45fb-91ee-7b728c174616?q=Titmouse).
Check that only the 3 rows of tags are displayed, with a "Show more tags" button. Try clicking on the button. The first opened tag should be focused, and the "See less" button should be displayed.
Check that this works for pages with other locales, and that the tags for media with fewer tags are displayed as before.

Checklist

• My pull request has a descriptive title (not a vague title likeUpdate index.md).
• My pull request targets the default branch of the repository (main) or a parent feature branch.
• My commit messages follow best practices.
• My code follows the established code style of the repository.
• I added or updated tests for the changes I made (if applicable).
• I added or updated documentation (if applicable).
• I tried running the project locally and verified that there are no visible errors.
• I ran the DAG documentation generator (if applicable).

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[zackkrida]

This works so well 🎉 I made one suggestion for code quality, but functionality-wise this is awesome.

[zackkrida]

@obulat I've drafted this so we can make the changes discussed in Slack:

• Add a TOGGLE_TAG_EXPANSION (or similar name) analytics event
• Finalize the language

[zackkrida]

LGTM.

[dhruvkb]

LGTM! I have a few suggestions but I will not block this PR.