Auto merge of #21048 - cbrewster:hash_change_history, r=asajeffrey

Track hash changes in session history

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Adds tracking of hash changes in the session history.

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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix #14970 fix #13437 (github issue number if applicable).

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