Port `LogContext` to Rust#19979

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erikjohnston wants to merge 7 commits into

erikj/logcontext-rust-p4-clean

Commits on Jul 20, 2026

tests: give mock homeservers a real string hostname

erikjohnston
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claude
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Commits on Jul 21, 2026

rust logcontext: don't write the thread-local slot from a scoped poll

erikjohnston
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claude
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