Documentation: best practices for writing samples

[Arlodotexe]

Describe the bug

We spent quite a bit of time creating tools that will speed up the developer experience when creating samples.

However, few will be able to use it to its fullest unless we supply docs. Essential parts such as generated / fully custom option panes and adding dependencies are more or less completely undocumented.

We also haven't published any guidance on creating the samples themselves. Users should be encouraged to break things up into multiple samples, keeping each one focused on a certain aspect of the control.

Additional context

No response

Help us help you

Yes, but only if others can assist.

[Arlodotexe]

@michael-hawker Since I designed these things, I can take this one and write something up.

We need to decide the best place for it to live, first. Wiki on GitHub? Markdown file in the repo? MSDocs website?