Support opening and comparing versions in viewer

[artonge]

Fix#39139
Fix#39140

Tests will be added in text as there is no default viewer handler that covers version comparison support for now

Screenshots

Clicking the version just opens a single preview

Comparing menu

• Comparing is available for any but the current version
  

• Clicking it will compare the picked with the current version
  

Todo

• Add option to disable sidebar viewer#1782
• feat: Compare files side by side viewer#1835
• BUG: Filter out image/video files
• BUG: Currently comparing when no viewer is open is not working
• Add screencasts
• Tested with:
  • Supporting version comparison
    • Text file
      • Default to source if fileid is undefined viewer#1806
      • Allow opening files outside of the file system in viewer text#2832
    • PDF
      • feat: Fix styling for version comparison files_pdfviewer#791
  • No version preview
    • Images
    • Video
    • Music
    • Files types not supported by the viewer

[juliusknorr]

/compile

[juliusknorr]

/compile

[juliusknorr]

/backport 5902325 to stable27

[backportbot-nextcloud]

The backport to stable27 failed. Please do this backport manually.

# Switch to the target branch and update it
git checkout stable27
git pull origin stable27
# Create the new backport branch
git checkout -b fix/foo-stable27
# Cherry pick the change from the commit sha1 of the change against the default branch# This might cause conflicts. Resolve them.
git cherry-pick abc123
# Push the cherry pick commit to the remote repository and open a pull request
git push origin fix/foo-stable27

More info at https://docs.nextcloud.com/server/latest/developer_manual/getting_started/development_process.html#manual-backport

[AndyScherzinger]

/backport 5902325 to stable27

[backportbot-nextcloud]

The backport to stable27 failed. Please do this backport manually.

# Switch to the target branch and update it
git checkout stable27
git pull origin stable27
# Create the new backport branch
git checkout -b fix/foo-stable27
# Cherry pick the change from the commit sha1 of the change against the default branch# This might cause conflicts. Resolve them.
git cherry-pick abc123
# Push the cherry pick commit to the remote repository and open a pull request
git push origin fix/foo-stable27

More info at https://docs.nextcloud.com/server/latest/developer_manual/getting_started/development_process.html#manual-backport

[AndyScherzinger]

Backport bot is no friend of mine nor of @juliushaertl 😭