feat: support fuzzy matching version numbers

[SalvatoreT]

Make it even easier to support migrating off other Ruby version managers.

Closes #474

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Basic case

If for some (cursed) reason someone just sets a non-fully qualified version

❯ cat .ruby-version
2

it'll resolve to either the newest one you have or (if none match) the newest one that matches

❯ asdf current ruby
Name            Version         Source                                       Installed
ruby            2.7.7           /Users/sal/Developer/asdf-ruby/.ruby-version true

Non MRI Ruby

Then I set the .ruby-version to JRuby 10.

❯ cat .ruby-version
jruby-10

And it resolves to the latest one

❯ asdf current ruby
Name            Version         Source                                       Installed
ruby            jruby-10.0.2.0  /Users/sal/Developer/asdf-ruby/.ruby-version true

❯ ruby --version
jruby 10.0.2.0 (3.4.2) 2025-08-07 cba6031bd0 OpenJDK 64-Bit Server VM 25+35-3488 on 25+35-3488 +indy +jit [arm64-darwin]

Not-yet-installed Ruby

I don't yet have Ruby 3.3.x on my machine.

❯ cat .ruby-version
3.3

so if I were to install a Ruby version, I'd get 3.3.10.

❯ asdf current ruby
Name            Version         Source                                       Installed
ruby            3.3.10          /Users/sal/Developer/asdf-ruby/.ruby-version false - Run `asdf install ruby 3.3.10`

[SalvatoreT]

@Stratus3D, please let me know what you think!