WorkerThreadPool (plus friends): Overhaul unlock allowance zones #826

Job	Run time
📊 Static checks / Code style, file formatting, and docs	1m 7s
🤖 Android / Editor (target=editor)	24m 37s
🤖 Android / Template arm32 (target=template_release, arch=arm32)	16m 53s
🍎 macOS / Editor (target=editor, tests=yes)	30m 26s
🤖 Android / Template arm64 (target=template_release, arch=arm64)	33m 9s
🐧 Linux / Editor w/ Mono (target=editor)	42m 36s
🍎 macOS / Template (target=template_release)	21m 33s
🐧 Linux / Editor with doubles and GCC sanitizers (target=editor, tests=yes, dev_build=yes, scu_build=yes, precision=double, use_asan=yes, use_ubsan=yes, linker=gold)	47m 52s
🐧 Linux / Editor with clang sanitizers (target=editor, tests=yes, dev_build=yes, use_asan=yes, use_ubsan=yes, use_llvm=yes, linker=lld)	36m 6s
🌐 Web / Template w/ threads (target=template_release, threads=yes)	23m 41s
🐧 Linux / Editor with ThreadSanitizer (target=editor, tests=yes, dev_build=yes, use_tsan=yes, use_llvm=yes, linker=lld)	32m 4s
🏁 Windows / Editor (target=editor, tests=yes)	49m 22s
🐧 Linux / Template w/ Mono (target=template_release)	26m 18s
🏁 Windows / Template (target=template_release)	35m 38s
🐧 Linux / Minimal template (target=template_release, everything disabled)	22m 32s
🌐 Web / Template w/o threads (target=template_release, threads=no)	23m 30s
🍏 iOS / Template (target=template_release)	12m 5s
🪲 Godot CPP / Build and test Godot CPP	8m 13s
	8h 7m 42s

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