## Summary of the Pull Request
This PR ensures that the list of recent searches in the Web Search
extension is updated immediately after a new item is added or when
settings controlling the number of items are changed.
- Refactors the Web Search extension history to keep it in memory after
being loaded at startup
- Adds an event to notify subscribers when the history changes
- Implements `IDisposable` to ensure that `WebSearchListPage`
unsubscribes from the event
- Moves responsibility for creating all list items to single class
(`WebSearchListPage`)
- Updated unit tests
-
## PR Checklist
- [x] Closes: #40548
- [ ] **Communication:** I've discussed this with core contributors
already. If the work hasn't been agreed, this work might be rejected
- [x] **Tests:** Added/updated and all pass
- [x] **Localization:** All end-user-facing strings can be localized
- [x] **Dev docs:** nothing
- [x] **New binaries:** none
- [x] **Documentation updated:** nope
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## Detailed Description of the Pull Request / Additional comments
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## Validation Steps Performed
