stacked_table: add context to error type, propagate lock error #94

Job	Run time
build (ubuntu-latest)	4m 52s
build (macos-13)	7m 58s
build (macos-14)	4m 21s
Check protos	23s
cargo-deny (advisories)	22s
build (windows-latest)	10m 23s
Build jj-lib without Git support	44s
cargo-deny (bans licenses sources)	22s
build (ubuntu-latest, --all-features)	5m 45s
Clippy check	2m 34s
Check that MkDocs can build the docs	23s
Check that MkDocs can build the docs with Poetry 1.8	23s
Check formatting	18s
	38m 48s

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