Implement search in Details views

[RobertJoonas]

Changes

• Refactor the structure of a metric on the frontend - use a Metric class with special creator functions.
• Create a higher-order component for keeping the query context (such as the query object itself and additional information such as revenueAvailable, importedDataInView, lastLoadTimestamp)
• Create a new BreakdownModal component that includes the search functionality, and make all current "Details" view modals to use it.
  • Note: some API endpoints (goals, countries, regions, cities) do not support a contains filter. This PR will start using the new BreakdownModal in those reports too, but the search is explicitly disabled via enableSearch={false} prop.

Tests

• [x] This PR does not require tests

Changelog

• [ ] Entry has been added to changelog

Documentation

• [ ] Docs have been updated

Dark mode

• [ ] The UI has been tested both in dark and light mode

[github-actions[bot]]

|Preview environment👷🏼‍♀️🏗️ | |:-:| | [PR-4318](https://pr-4318.review.plausible.io)

[aerosol]

Well done, this is really cool. WYT about treating the search input with autofocus?