[Bug]: field numbers no longer warn when duplicated

[Stanzilla]

Describe the bug

I sadly don't remember when it was working the last time but on 0.63 of the VSC extension I no longer get warnings when I have duplicated field numbers in a model definition.

Reproduction

  model MatchOptions {
    @field(1)
    maps?: Options;

    @field(2)
    locations?: Options;

    @field(3)
    roles?: Options;

    @field(3) // this should warn/error
    verified_matching?: boolean;
  }

Checklist

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• The provided reproduction is a minimal reproducible example of the bug.