Sync query history

I switch between a laptop and a desktop pretty regularly, and I often find myself looking for a query in the history only for it to be on another machine. It would be convenient for me if the query history could be synced between multiple computers automatically (using iCloud perhaps?).

The issue names no files, tests, or entry points. Start by locating how query history is stored and reviewing the project's available mechanisms for syncing it between computers; clarify the sync service, privacy expectations, conflict handling, and acceptance criteria before implementation.

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