Complete HaskellTestCreator availability and presentation logic

[ForNeVeR]

Problem

HaskellTestCreator has unresolved TODOs in action availability checks and location string handling.

Why it matters

The test creation action may appear in unsupported contexts and exposes placeholder UI text.

Affected code locations

• haskeletor/src/main/scala/me/fornever/haskeletor/testIntegration/HaskellTestCreator.scala

  Line 29 in d71af7e

  //TODO Is there any check we should do here?

• haskeletor/src/main/scala/me/fornever/haskeletor/testIntegration/HaskellTestCreator.scala

  Line 49 in d71af7e

  //TODO What's this?