Improve error message when contract calls its own method

[anton-trunov]

close #1491

We add ABI methods to the namespace (this is going to be useful for the super-ABI feature) and filter out same contract method calls during method application typechecking, instead of not adding ABI methods to the namespace and providing a bit confusing error message like No method named "method1" found for type "contract".

Description

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).
• 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.