fix(os-compatibility): normalize file paths and enforce eol consistency

[muaydin]

Problem

• Tests were failing or behaving inconsistently on different operating systems due to improper file path normalization.
• End-of-line (EOL) conflicts were causing unnecessary formatting diffs in collaborative workflows.

Solution

• Updated the testFile variable in the test runner to normalize paths by replacing backslashes () with forward slashes, ensuring cross-platform compatibility.
• Added the Prettier rule 'prettier/prettier': ['error', { endOfLine: 'auto' }] to align EOL behavior with the host environment, avoiding platform-specific conflicts.

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