Check for type aliases when implementing traits

[jjcnn]

Description

Fixes #6329 .

Status:

• Testcase added. The compiler correctly rejects the program.
• The error message has been improved to use the aliased name when appropriate
• TODO: There are other errors in TraitMap::insert that should be similarly improved.
• TODO: Check if we can fix this generally by not introducing new types when declaring a type alias.

Checklist

• I have linked to any relevant issues.
• I have commented my code, particularly in hard-to-understand areas.
• I have updated the documentation where relevant (API docs, the reference, and the Sway book).
  • If my change requires substantial documentation changes, I have requested support from the DevRel team
• I have added tests that prove my fix is effective or that my feature works.
• I have added (or requested a maintainer to add) the necessary Breaking* or New Feature labels where relevant.
• I have done my best to ensure that my PR adheres to the Fuel Labs Code Review Standards.
• I have requested a review from the relevant team or maintainers.

[codspeed-hq]

CodSpeed Performance Report

Merging #6875 will not alter performance

_{Comparing jjcnn/unalias_type_id_in_trait_map_unification (c85d708) with master (fccc8a9)}

Summary

✅ 22 untouched benchmarks