isUriLikeOverride function
Returns whether value explicitly uses a URI scheme rather than a local
path. Windows drive paths and WSL/UNC paths are intentionally local.
Implementation
bool isUriLikeOverride(String value) {
if (RegExp(r'^[A-Za-z]:[\\/]').hasMatch(value)) return false;
if (value.startsWith(r'\\') || value.startsWith('//')) return false;
return RegExp(r'^[A-Za-z][A-Za-z0-9+.-]*:').hasMatch(value);
}