Reject duplicate versions by default

[dexman545]

Is your feature request related to a problem? Please describe.
Previously, when using automated uploads Modrinth would reject identical versions. This is no longer the case, causing automated uploads relying on this feature to upload multiple of the same version.

Describe the solution you'd like
Fail or skip the upload task when the version is already present on Modrinth

Describe alternatives you've considered
This is fairly easy to work around with Outlet, as it already has a way to query Modrinth for an existing version for a given set of loaders/mc versions, making skipping the task an onlyIf call.

Additional context
Add any other context or screenshots about the feature request here.

[Deftu]

Identical version numbers are intended. I guess an API input disabling them could be implemented? But aside from that the current functionality is how things should stay imo.

[Siphalor]

I'd suggest rejecting by default, but allowing behavior through a config option, either:

• REJECT (default)
• DUPLICATE (multiple of the same versions will be uploaded)
• UPDATE (will update an existing version's metadata, like supported MC versions or changelog)
• APPEND (based on #23, would add the new files to the existing version)