Remove kibana yml settings workaround in input control vis

[flash1293]

In #63443 it was necessary to implement a workaround for passing some kibana.yml settings to the client using a new API route. This should be removed and replaced by the core exposeToBrowser functionality. This depends on #66085

Locations in code:

• https://github.com/elastic/kibana/blob/master/src/plugins/input_control_vis/server/index.ts
• https://github.com/elastic/kibana/blob/master/src/plugins/input_control_vis/public/plugin.ts#L69

[elasticmachine]

Pinging @elastic/kibana-app (Team:KibanaApp)

[flash1293]

cc @ThomThomson @lizozom

This might not be the right approach after all - soon there will be a specific API to fetch auto complete values, so we can just use that instead of using the search service in a hacky way.

[lizozom]

The API data.autocomplete.getValueSuggestions already exists.
If #81515 gets merged, it will also support the useTimeFilter option, which you need to support the existing API.

[Heenawter]

I think it's fair to close this issue - we don't plan on changing anything on the legacy input controls, and all hacky code will get completely removed once we can finally remove them for good 👍