Debian Update to bookworm release & Nextcloud sync feature & Obisidan latest release

[drdada]

• Update Debian to Bookworm
• Nextcloud sync feature can now sync your MD files with your Nextcloud instance
  • Env-file contains the credentials for Nextcloud
  • Sync trigger have to be done manually (right click on the desktop)
• Dockerfile now download the latest release directly
• Update Readme regarding the clipboard menu

[bioluks]

Yesterday I tried to build the image but I'm not able to pull ghcr.io/linuxserver/baseimage-kasmvnc:debianbullseye since linuxserver does not publish images with the tag debianbullseye anymore. Tried it with ghcr.io/linuxserver/baseimage-kasmvnc:debianbookworm and everything worked flawlessly. For this image to build successfully from now on this PR needs to be merged, at least the part with debianbookworm.
But I see that in this PR you removed various references to @sytone why is that? He is still merging the pull-requests and this repo is active - maybe behind on updates but still maintained. You even changed docker image paths to your own repo but don't provide the image there. Aside from that I find the Nextcloud Sync feature cool if it works.