fix: remove TProject generic shadowing in binPath (CHK-001)

[scalvert]

Summary

• Removes inner `` generic from `binPath` function type
• The inner generic was shadowing the outer interface generic, causing consumers with custom project subclasses to lose type specificity in the `binPath` callback
• The callback now correctly references the outer `TProject` generic, so a consumer using `createProject: () => new CustomProject()` will receive `CustomProject` (not just `BintasticProject`) in their `binPath` function

Checklist item

Closes CHK-001 from EVAL-CHECKLIST.md

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