[core] Add CodSpeed C++ benchmarks for protobuf, main loop, and helpers (#14878)

script/clang-tidy

@@ -231,6 +231,9 @@ def main():
 
     cwd = os.getcwd()
     files = [os.path.relpath(path, cwd) for path in git_ls_files(["*.cpp"])]
+    # Exclude benchmark files — they require google benchmark headers not
+    # available in the ESP32 toolchain and use different naming conventions.
+    files = [f for f in files if not f.startswith("tests/benchmarks/")]
 
     # Print initial file count if it's large
     if len(files) > 50: