[stable31] feat: auto replace latest urls for older releases

[backportbot]

Backport of #14230

Warning, This backport's changes differ from the original and might be incomplete ⚠️

Todo

• Review and resolve any conflicts
• Review and verify the backported changes
• Amend HEAD commit to remove the line stating to skip CI

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

[skjnldsv]

@copilot fix the backport. See what the original PR did and ensure continuity.
Make sure to tackle the todo in the PR description.

[Copilot]

@copilot fix the backport. See what the original PR did and ensure continuity.
Make sure to tackle the todo in the PR description.

Fixed in 25fdf1e. The backport was missing TODO ON RELEASE comment removals from several files. I've removed them from all remaining files:

• admin_manual/apps_management.rst
• admin_manual/index.rst
• admin_manual/occ_command.rst (stable31-specific, split from occ_apps/occ_files on master)
• admin_manual/webhook_listeners/index.rst (stable31-specific)
• admin_manual/windmill_workflows/index.rst (stable31-specific)
• user_manual/groupware/sync_ios.rst
• user_manual/groupware/sync_gnome.rst (stable31-specific)
• user_manual/files/deleted_file_management.rst
• developer_manual/client_apis/OCS/ocs-taskprocessing-api.rst

The conf.py changes (validation, logging, replace_latest function, setup()) were already correctly backported. No more TODO ON RELEASE comments remain in the RST files.