refactor: simplify boolean comparisons and improve clarity

[forkfury]

Description

Problem*

Multiple code segments used redundant comparisons like == true or == false, which clutter readability and go against idiomatic style.

Summary*

• Replaced == true and == false with direct boolean usage (e.g., if flag == true → if flag).

• Updated several assert(...) == true statements to cleaner assert(...).

• Simplified conditionals across Noir standard library and test programs.

• Improved error messaging and removed redundant logic in a JS preprocessor.

Additional Context

Documentation*

Check one:

• No documentation needed.
• Documentation included in this PR.
• [For Experimental Features] Documentation to be submitted in a separate PR.

PR Checklist*

• I have tested the changes locally.
• I have formatted the changes with Prettier and/or cargo fmt on default settings.

[github-actions]

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