The code that supports HTML field history has been moved from the website editor area into the shared HTML editor module. This is an internal cleanup that makes the functionality easier to maintain and reuse without changing the user experience.

Move html_field_history_mixin, and related python files to the html_editor module.


task-5045242


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The spreadsheet-related test setup was simplified now that all tests use the newer Hoot framework. This reduces hidden test interference between modules and helps keep future spreadsheet changes safer and easier to maintain.

All tests have been converted to Hoot now. And each hoot test suite only runs with its dependencies. Patches in other modules no longer impacts `web` tests.