normalizeToolResult function
Normalizes any tool handler return value to a ToolResult.
Implementation
ToolResult normalizeToolResult(dynamic result) {
if (result == null) {
return const ToolResultFailure(error: 'tool returned no result');
}
if (result is ToolResult) return result;
if (result is String) return ToolResultSuccess(result);
return ToolResultSuccess(result.toString());
}