ipfixprobe.cpp: handle SIGABRT to support libunwind-based diagnostics

[SiskaPavel]

Summary

Handle SIGABRT alongside SIGSEGV to improve diagnostic capabilities during abnormal termination, especially when triggered by libunwind, sanitizers, or runtime assertions.

Details

This PR updates the signal handling mechanism to treat SIGABRT similarly to SIGSEGV.
When the application receives SIGABRT (e.g. due to abort(), failed assert(), or sanitizers), it now properly invokes st_dump() to capture diagnostic output.
The handler then exits using exit(EXIT_FAILURE) instead of abort() to prevent recursive signal triggering.

This ensures that crashes triggered by internal runtime mechanisms (like libunwind, ASan, or failed invariants) are logged consistently.

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✅ Checks

• CI pipeline passes (build, tests, lint, static analysis)
• New code follows clang-tidy rules
• The change is clearly related to a specific issue / requirement
• The PR is rebased on the latest master
• No unrelated changes are included
  - [ ] Documentation (e.g. Doxygen) is updated if needed
  - [ ] Relevant documentation was updated (if needed)

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