fix(examples): raise proper SIGSEV instead of undefined behavior

[markushi]

Description

Fix native sample to raise a proper SIGSEV signal instead of causing undefined behavior.

Motivation and Context

The current implementation causes undefined behavior in release builds, causing an endless loop of "Sending message." instead of actually producing a SIGSEV.

How did you test it?

Verified the native sample raises SIGSEV correctly.

Checklist

• No breaking change or entry added to the changelog.

#skip-changelog

[markushi]

Thank you @supervacuus for root-causing this!

[supervacuus]

Just to be clear: my point wasn't necessarily to replace the "intentional UB" with an explicit user-space raise, but especially for a sample that only wants to trigger a native "crash" to demo its handling, that can be a solid alternative 👍