Introduce `ControlExtensions` to simplify frequently needed iterating tasks

### Background and motivation

There are a lot of cases, where we need to recursively traverse through the controls collection (up or down), to either process a collection of certain controls or find a specific control in the tree. This is, where the typical WinForms developer invents the wheel for their apps for the gazilion-th time.

To that end, we suggest introducing the following extension class to make those tasks super-convenient, and make sure, that we do not allocate anything during operation.

Note:
PR would be a side-product of one of the .NET Conf Demos and ready to go immediately.
@merriemcgaw, @lonitra

@JeremyKuhne: If we want to further discuss the concept of a more granular base-layout type, this API would be super-easy to adapt to that and also the perfect icing on that cake.

### API Proposal

```csharp
public static IEnumerable ChildControls(this Control control)
public static IEnumerable ChildControls(this Control control) where T : Control
public static Control FirstChild(this Control control, Func? predicate = default)
public static T FirstChild(this Control control, Func? predicate = default) where T : Control
public static T? FirstChildOrDefault(this Control control, Func? predicate = default) where T : Control
public static IEnumerable AscendantControls(this Control control)
public static IEnumerable AscendantControls(this Control control, Func? predicate = default) where T : Control
public static Control FirstAscendant(this Control control, Func? predicate = default)
public static Control? FirstAscendantOrDefault(this Control control, Func? predicate = default)
public static T FirstAscendant(this Control control, Func? predicate = default) where T : Control
public static T? FirstAscendantOrDefault(this Control control, Func? predicate = default) where T : Control
public static IEnumerable DescendantControls(this Control control)
public static IEnumerable DescendantControls(this Control control, Func? predicate = default) where T : Control
public static Control FirstDescendant(this Control control, Func? predicate = default)
public static T FirstDescendant(this Control control, Func? predicate = default) where T : Control
public static Control? FirstDescendantOrDefault(this Control control, Func? predicate = default)
public static T? FirstDescendantOrDefault(this Control control, Func? predicate
public static Control Root(this Control control)
```

### API Usage

Self-Explaining.

### Alternative Designs

_No response_

### Risks

None.

### Will this feature affect UI controls?

Only easier usage and help with discoverability.