:sig
String capture_backtrace_string(u32 max_frames = 32, u32 skip_frames = 0)

:params
max_frames : maximum number of frames to capture
skip_frames : number of newest frames to omit
return value : formatted backtrace string

:see
>runtime
backtrace_frames_string
signal_name

:content
Captures and formats a native backtrace for the current call stack.

This helper is for diagnostics. It is used by runtime error reporting paths and can also be useful in local debugging pages.

Example:

```uce
String trace = capture_backtrace_string(16, 0);
print("<pre>", html_escape(trace), "</pre>");
```