feat: new runtime info API

[darvld]

Summary

This PR introduces the HostRuntime API, which provides information about the runtime to engine plugins. Use the PolyglotEngineConfiguration.hostRuntime property to access it:

/** Provides information about the runtime hosting the application. */
@DelicateElideApi public interface HostRuntime {
  /** The name of this runtime, which is used in string representations and for debugging purposes. */
  public val name: String

  /** The version spec of this runtime, wrapped to allow version comparisons using regular operators. */
  public val version: Version?

  /** An optional variant name for this runtime. Some engines like GraalVM differentiate between runtime variants. */
  public val variant: String?
}

The HostRuntime.on extension provides conditional execution of code based on the version of the current runtime, compared with the specified target version (or version range). The GraalVMRuntime companion provides a few version constants representing known GraalVM versions (GVM_23 and GVM_23_1):

fun configureOptions(configuration: PolyglotEngineConfiguration) {
  // enable some options only for GraalVM 23.0 and previous versions
  configuration.hostRuntime.on(GVM_23.andLower()) {
    enableOption("engine.Inlining")
  }
}

[sgammon]

merging with #445