CI: bump `clippy` to v1.84; enable `--all-features` #77

Job	Run time
minimal-versions	0s
set-msrv / set-msrv	6s
no_std (1.81.0, thumbv7em-none-eabi)	24s
test (1.81.0)	37s
cross (powerpc-unknown-linux-gnu, 1.81.0)	54s
no_std (1.81.0, wasm32-unknown-unknown)	24s
test (stable)	37s
cross (powerpc-unknown-linux-gnu, stable)	47s
no_std (stable, thumbv7em-none-eabi)	20s
no_std (stable, wasm32-unknown-unknown)	22s
	4m 31s

Provide feedback