fix: properly lex imports in OPL

[hperl]

Related issue(s)

Closes #1040

Checklist

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  introduces a new feature.
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Further Comments

[zepatrik]

So are imports now considered string literals, but their value is not used? Don't really understand how this works now 😅

[hperl]

So are imports now considered string literals, but their value is not used? Don't really understand how this works now sweat_smile

In the lexing phase, we just want to generate a token stream from the input. So import { Foo, Bar, Baz } from '@ory/keto-namespace-types' becomes this:

[
  "'import'",
  "{",
  "'Foo'",
  ",",
  "'Bar'",
  ",",
  "'Baz'",
  "}",
  "'from'",
  "'@ory/keto-...'",
  "EOF"
]

In the parsing phase, this stream will be complete ignored because we just skip until we find a class keyword.