style(cpp): apply clang-format Google style to C++ sources

Auto-format irk_capture.h and irk_capture.cpp with clang-format
--style=Google to satisfy the CI C++ Format Check. Changes are
purely cosmetic (brace-initializer spacing, single-line function
collapsing, line-wrapping of long declarations) — no logic changes.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: DerekSeaman