Add notice for `Protocol c => Vec n a` utilities #5676

Job	Run time
license-check	9s
bittide-instances synthesis matrix generation	24s
Build dependencies	4m 3s
bittide-instances hardware-in-the-loop test matrix generation	23s
Basic linting	36s
bittide-experiments unittests	56s
Bittide tests	17s
Firmware Support Unit Tests	1s
Rust Lints	1s
bittide-instances doctests	1s
Firmware Limit Checks	1s
bittide-instances unittests	1s
Host Tools Unit Tests	1s
synth (fullMeshHwCcTest, test)	1s
synth (fullMeshSwCcTest, test)	1s
synth (linkConfigurationTest, test)	1s
synth (safeDffSynchronizer, hdl)	1s
synth (transceiversUpTest, test)	1s
synth (vexRiscvTest, test)	1s
synth (vexRiscvTcpTest, test)	1s
HITL	1s
Generate clock control report	1s
All jobs finished	1s
	7m 4s

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