Function validate_coverage_id 

pub fn validate_coverage_id(
    coverage_id: &str,
) -> Result<(), CoverageLayoutError>

Validates that a coverage ID meets security and format requirements.

A valid coverage ID must:

• Not be empty and not exceed 128 characters
• Not contain path separators (/, \\) or .. sequences
• Only contain ASCII alphanumeric characters, dots, underscores, and hyphens