More hold mismatch fixes

[zippy]

PR summary

• Fixed memory leak in various timeout conditions of direct messages
• Fixed holding-list/CAS mismatch potential in various error conditions when sim2h requests aspect holding
• Fixed bug in holding remove link before add-link validation complete

testing/benchmarking notes

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followups

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changelog

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- summary of change [PR#1234](https://github.com/holochain/holochain-rust/pull/1234)

documentation

• this code has been documented according to our docs checklist