client: switch to ScriptBuf api #30

Job	Run time
build (ubuntu-latest, 1.63.0)	3m 9s
build (ubuntu-latest, stable)	1m 42s
build (ubuntu-latest, beta)	1m 38s
build (ubuntu-latest, nightly)	1m 38s
build (macos-latest, 1.63.0)	2m 28s
build (macos-latest, stable)	1m 28s
build (macos-latest, beta)	1m 16s
build (macos-latest, nightly)	1m 29s
build (windows-latest, 1.63.0)	4m 20s
build (windows-latest, stable)	2m 47s
build (windows-latest, beta)	2m 26s
build (windows-latest, nightly)	2m 25s
	26m 46s

Provide feedback