Feature: #78760 - Resizable Navigation Component

See forge#78760

Description

The Navigation Component in TYPO3's backend, which shows e.g. the Page Tree or the folder tree (within the file list module), can be resized via Drag&Drop or via a button, which is layered within the Navigation Component itself. A similar functionality was previously put in the top bar on the left, for mobile devices, but was removed in favor of this new solution.

The size of the navigation component is now stored in the users' "uc" configuration to be persistent during various logins and kept for multiple sessions.

Impact

TYPO3 now allows to not just resize the pagetree component, but any navigation component (just like iframes).

When the component is collapsed, an icon is shown to indicate that the navigation can be re-opened.

This makes it easier for editors to have a distraction-free management interface when needed.