cbuffer/cgetbuffer/caddbuffer doesn't accept a range #16501

Job	Run time
linux (tiny, clang, native)	2m 1s
linux (tiny, gcc, native)	1m 42s
windows (HUGE, msvc, no, no, x64, stable)	6m 31s
linux (normal, clang, native)	5m 0s
macos (tiny, macos-12)	1m 9s
windows (HUGE, mingw, yes, yes, x86, stable, yes)	10m 45s
linux (normal, gcc, native)	4m 44s
macos (tiny, macos-14)	35s
linux (huge, clang, native)	9m 22s
windows (HUGE, msvc, no, yes, x86)	8m 15s
linux (huge, gcc, native)	10m 22s
windows (HUGE, mingw, yes, no, x64, yes)	10m 28s
macos (normal, macos-12)	6m 3s
linux (tiny, clang, nogui)	1m 32s
windows (NORMAL, msvc, yes, no, x86)	6m 21s
macos (normal, macos-14)	4m 49s
linux (tiny, gcc, nogui)	1m 30s
windows (NORMAL, mingw, no, yes, x64)	8m 50s
macos (huge, macos-12)	15m 25s
linux (normal, gcc, i386, ./src/shadow)	5m 58s
macos (huge, macos-14)	12m 37s
windows (TINY, msvc, yes, yes, x64)	1m 32s
linux (huge, gcc, uchar, testgui, true, dynamic)	8m 35s
windows (TINY, mingw, no, no, x86)	2m 31s
linux (huge, clang, asan, 5.1)	15m 46s
linux (huge, gcc, unittests, true)	2m 3s
linux (normal, gcc, vimtags)	1m 52s
	2h 46m 18s

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