Fixes #33347 - Fix settings index API

Fixes #33280 - category for DSL defined settings

Fixes #31638 - Adds host status overview page

refs #32287 - Restrict search operators for Settings

Search method from 'setting index loads from registry' PR [0]
support only few search operators, `SearchBar` component
at Settings page should not display other unsupported operators

[0] https://github.com/theforeman/foreman/pull/8438

Fixes #32415 - access only through SettingRegistry

Update and read the settings through SettingRegistry.
Adds a layer between controller and Model.
SettingRegistry is proxying the value parsing method to the model.

This lifts blocker for settings without DB record.

Fixes #32286 - new settings definition DSL

Introduces a new DSL to define settings, so we don't need to define
STI classes for every setting category and we have more control over
settings from the plugins.

Fixes #32287 - setting index loads from registry

The values provided on the Setting index page are now served from
registry, with simple search API, that can be easily improve to support
more querying features.

Fixes #30862 - introduce SettingRegistry (#8002)

SettingRegistry keeps all the setting information as set of SettingPresenters in memory.
This registry should be the public API for accessing setting values and keeps all the information about settings.
That will allow dropping all information except `name` and `value` from database....

Refs #31285 - use Ruby 1.9 style Hash

Fixes #31285 - setting timestamps for API

Presenter doesn't include Setting timestamps, what resulted in a regressision,
the timestamps were not present for the API responses anymore.
This brings the timestamps back temporarily.