Roadmap for version 5

[susnux]

Currently stable 4.2.0 is scheduled to be released 10th September so we can ship it with Nextcloud 27.1.0.

5.0.0 targets Nextcloud 28 and nextcloud-vue 8. So my plan is:

1. Merge the DialogBase and DialogButton components as NcDialog and NcDialogButton in the Vue library
2. Get the text classes merged for NcButton so we can remove our hack on the file list table headers
3. Use the components from the vue library and release

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Currently 4.2 contains the new filepicker for Nextcloud 27 (@nextcloud/vue version 7).
So version 5 will be a breaking change to support upcoming Nextcloud 28 with @nextcloud/vue version 8.

For this I would like to drop the legacy entry point by moving it to server core. As we can deprecate it there and remove it at some point without having to keep it in the library all the time and maintaining three different ways to spawn the picker in this library.

Instead I would like to adapt the filepicker builder for the new filepicker instead of wrapping the new interface in the legacy wrapper first. This would allow even more fine grained control over e.g. callbacks and buttons.
But this would be a breaking change on the builder API so I would do this on version 5 only.