libf3d: Improve API for [[nodiscard]] and missing this* return #7493

Job	Run time
Update LFS data cache	1m 13s
external-build	2m 36s
android (armeabi-v7a)	2m 43s
android (arm64-v8a)	2m 57s
android (x86)	2m 37s
android (x86_64)	2m 42s
linux (commit, standard)	9m 31s
linux (v9.4.0, standard)	9m 34s
macos (commit)	16m 0s
windows (commit, no-static)	15m 29s
linux (v9.3.1, standard)	7m 2s
macos (v9.4.0)	18m 45s
macos_arm (commit, no-bundle, no-static)	9m 41s
windows (v9.4.0, no-static)	15m 50s
linux (v9.2.6, standard)	6m 21s
macos (v9.3.1)	14m 6s
macos_arm (v9.4.0, no-bundle, no-static)	7m 53s
windows (v9.3.1, no-static)	11m 58s
linux (egl, commit, raytracing, optional-deps, no-exclude-deprecated, egl, no-static)	9m 55s
macos (v9.2.6)	16m 14s
macos_arm (v9.3.1, no-bundle, no-static)	7m 14s
windows (v9.2.6, no-static)	12m 46s
linux (osmesa, commit, raytracing, optional-deps, no-exclude-deprecated, osmesa, no-static)	9m 9s
macos_arm (commit, bundle, no-static)	8m 26s
windows (commit, static)	14m 47s
linux (exclude_deprecated, commit, raytracing, optional-deps, exclude-deprecated, auto, no-static)	9m 48s
macos_arm (commit, no-bundle, static)	8m 39s
coverage	9m 29s
linux (no_optional_deps, commit, no-raytracing, no-optional-deps, no-exclude-deprecated, auto, no...	5m 57s
linux (static_libs, commit, no-raytracing, optional-deps, no-exclude-deprecated, auto, static)	8m 54s
python-packaging (ubuntu-latest)	4m 36s
sanitizer (address)	12m 46s
python-packaging (windows-latest)	6m 49s
sanitizer (thread)	14m 24s
python-packaging (macos-13)	4m 46s
sanitizer (undefined)	10m 0s
static-analysis	7m 9s
	5h 38m 46s

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