Fix some clang-tidy issues in headers #3325

Job	Run time
macOS (shared, clang)	9m 58s
macOS (amalgamation, clang)	5m 48s
Clang Tidy	55s
Linux (gcc, shared)	8m 43s
Linux (gcc, amalgamation)	7m 50s
Linux (gcc, static)	9m 4s
Linux (clang, shared)	8m 30s
Analysis (coverage, gcc, ubuntu-22.04)	12m 18s
Analysis (sanitizer, msvc, windows-2022, jom)	12m 8s
Analysis (sanitizer, clang, ubuntu-22.04)	12m 18s
Analysis (sanitizer, gcc, ubuntu-22.04)	12m 17s
Analysis (valgrind, gcc, ubuntu-22.04)	12m 18s
Analysis (fuzzers, gcc, ubuntu-22.04)	12m 17s
Analysis (lint, gcc, ubuntu-22.04)	42s
Analysis (format, gcc, ubuntu-22.04)	52s
Special (examples, gcc, ubuntu-22.04)	7m 51s
Special (minimized, gcc, ubuntu-22.04)	2m 11s
Special (bsi, gcc, ubuntu-22.04)	5m 39s
Windows (shared, x86_64, windows-2022)	11m 13s
Windows (static, x86_64, windows-2022)	9m 42s
Windows (amalgamation, x86_64, windows-2022)	12m 12s
Windows (shared, x86, windows-2022)	11m 14s
Cross (cross-i386, gcc, ubuntu-22.04)	4m 20s
Cross (cross-arm32, gcc, ubuntu-22.04)	5m 4s
Cross (cross-arm64, gcc, ubuntu-22.04)	4m 21s
Cross (cross-ppc64, gcc, ubuntu-22.04)	3m 38s
Cross (cross-riscv64, gcc, ubuntu-22.04)	3m 25s
Cross (cross-android-arm32, clang, ubuntu-22.04)	4m 42s
Cross (cross-android-arm64, clang, ubuntu-22.04)	4m 53s
Cross (static, gcc, windows-2022, mingw32-make)	1m 57s
Cross (cross-ios-arm64, clang, macos-13)	6m 7s
Cross (emscripten, emcc, ubuntu-22.04)	3m 5s
	3h 47m 32s

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