Detect links with fragments as internal links

[max-nextcloud]

Describe the bug Internal links are handled specially so they work for public shares etc.

Also apply this special handling if a link has a fragment specified.

To Reproduce Steps to reproduce the behavior:

1. Drag a page into the editor for another page
2. See the link preview and follow the link - works nicely
3. Change the link to include a fragment - i.e. append #hello.
4. Try again - no more preview link opens in new tab.

Expected behavior The link with a fragment should behave just like one without - ideally even taking you to the right section on the linked page.

Screenshots

Without fragment:

with fragment:

Server details: Tested on cloud.nextcloud.com with Nextcloud 32.0.0 and Collectives 3.2.0