rune: Define and document more protocols #1787

Job	Run time
clippy	2m 3s
msrv	1m 34s
docs	3m 17s
nightly	3m 16s
rustfmt	16s
basics	1s
no_std (ubuntu-latest, minimal)	1m 12s
build_feature (alloc)	3m 31s
test_miri (rune, runtime:: hir::arena:: --skip runtime::vm:: --skip runtime::vm_execution:: )	2m 28s
no_std (macos-latest, minimal)	1m 6s
build_feature (cli)	4m 2s
test_doc	6m 4s
test_miri (rune-alloc)	6m 0s
build_feature (cli,doc)	3m 49s
test_lib	4m 9s
build_feature (cli,fmt)	4m 9s
test_rune	2m 53s
wasm	1m 6s
build_feature (doc)	3m 42s
build_feature (workspace)	3m 23s
build_feature (languageserver)	3m 48s
build_feature (byte-code)	3m 30s
build_feature (capture-io)	3m 43s
build_feature (emit)	3m 25s
	1h 12m 27s

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