Function collect_with_version

src/diagnostics/unused_variables.rs:524–532

Helper: same as `collect` but with a specific PHP version.

(php: &str, version: PhpVersion)

    /// Helper: same as `collect` but with a specific PHP version.
    fn collect_with_version(php: &str, version: PhpVersion) -> Vec<Diagnostic> {
        let backend = Backend::new_test();
        backend.set_php_version(version);
        let uri = "file:///test.php";
        backend.update_ast(uri, php);
        let mut out = Vec::new();
        backend.collect_unused_variable_diagnostics(uri, php, &mut out);
        out
    }

    // ═══════════════════════════════════════════════════════════════
    // PHP version gating for catch variables