feat: Document new API for occ reserved options

[come-nc]

☑️ Resolves

See nextcloud/server#46115

🖼️ Screenshots

[joshtrichards]

Should we add any references to these options within the Admin Manual at this point? I was thinking the general occ overview: https://docs.nextcloud.com/server/latest/admin_manual/configuration_server/occ_command.html

[come-nc]

/backport to stable30

[backportbot]

The backport to stable30 failed. Please do this backport manually.

# Switch to the target branch and update it
git checkout stable30
git pull origin stable30
# Create the new backport branch
git checkout -b backport/12090/stable30
# Cherry pick the change from the commit sha1 of the change against the default branch# This might cause conflicts, resolve them
git cherry-pick 9f00fee5
# Push the cherry pick commit to the remote repository and open a pull request
git push origin backport/12090/stable30

Error: No changes found in backport branch

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Learn more about backports at https://docs.nextcloud.com/server/stable/go.php?to=developer-backports.