Ability to `--bump` to non-patch pre-release (e.g. `2.0.0` -> `2.1.0-rc.1`)

Say for example the version is 2.0.0 for a cargo project, and we want to make a rc for a minor version, i.e 2.1.0-rc , but when using
`cargo set-version --bump rc` , the follow happens:
`2.0.0` ---> `2.0.1-rc.1`

Expected bump: `2.0.0` ---> `2.1.0-rc.1`

So maybe adding a feature which allows us to make a release candidate of all the three semvers (major minor patch) would be useful!

If this feature already exists, do let me know!

Start by tracing the cargo set-version --bump rc command and its version-bumping logic. Confirm how it currently turns 2.0.0 into 2.0.1-rc.1, then define completion as supporting the requested 2.1.0-rc.1 result and equivalent major, minor, and patch release-candidate bumps.

Written by the indexing model from the issue text.