feat(compiler)!: Force aqua header [LNG-308]

[InversionSpaces]

Description

Force aqua header for all aqua source files, deprecate module keyword.

Implementation Details

• Simplify header parsing
• Raise semantic errors on absence of a header, module keyword and incorrect header position.

Checklist

• Corresponding issue has been created and linked in PR title.
• Proposed changes are covered by tests.
• Documentation has been updated to reflect the changes (if applicable).
• I have self-reviewed my code and ensured its quality.
• I have added/updated necessary comments to aid understanding.

Reviewer Checklist

• Tests have been reviewed and are sufficient to validate the changes.
• Documentation has been reviewed and is up to date.
• Any questions or concerns have been addressed.

[linear]

LNG-308 Deprecate `module`, force `aqua` header