Primitive accessibility issue filtering helpers.

The crate stays generic and dependency-free so it can be reused across different UI or document models.

Examples

use use_accessibility_check::{
    AccessibilityIssue, AccessibilitySeverity, filter_by_severity, has_errors, has_warnings,
    issue_count,
};

let issues = [
    AccessibilityIssue {
        code: String::from("contrast"),
        message: String::from("Low contrast"),
        severity: AccessibilitySeverity::Warning,
    },
    AccessibilityIssue {
        code: String::from("label"),
        message: String::from("Missing label"),
        severity: AccessibilitySeverity::Error,
    },
];

assert!(has_warnings(&issues));
assert!(has_errors(&issues));
assert_eq!(filter_by_severity(&issues, AccessibilitySeverity::Warning).len(), 1);
assert_eq!(issue_count(&issues), 2);