Expose Preview direct links in sharing UI

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Is your feature request related to a problem? Please describe.
The preview feature (https://github.com/nextcloud/server/pull/6599) has been implemented since long ago, but hasn't been made available in the UI since then except from the landing page of a default public share link. If one wants to provide links to their files as previews, they should KNOW that this feature exists first, then append /preview at the end of the share link they're provided by NC, or use the link they're provided by NC first, then copy the link below the picture so they can share it right after. This isn't user-friendly.

Describe the solution you'd like
NC should provide an option directly in its server UI to transform a link into a preview link. For example and more prominently, from its drop-down "Three dots" link-options menu (as shown in picture below).

Describe alternatives you've considered
Preview and Download public share links could be made as the defaults if the user/instance decides to.

Additional context
When this feature was just implemented, this already created some confusion: https://github.com/nextcloud/server/pull/6599#issuecomment-332330093
Another user here being confused: https://github.com/nextcloud/server/issues/2523#issuecomment-1375275031
Another explaining how the whole process is unnecessarily long: https://github.com/nextcloud/server/issues/16239#issuecomment-529357184
An almost exact issue exists here: https://github.com/nextcloud/server/issues/10545 but has been closed since, while receiving several comments.
A similar issue regarding the Download feature of some share links is discussed here: https://github.com/nextcloud/server/issues/35304

Start by reviewing the existing preview implementation in pull request #6599 and the current server sharing UI, especially its three-dots link-options menu. Check the related issues for expected preview and download-link behavior; done means users can generate or transform a share link into a preview link directly from the UI.