Blog post: Something about guidelines and baselines

[fertrig]

This is pending. I want a post that highlights the importance of guidelines and baselines.

Describe that Monarch preview isolation makes it possible to show guidelines and baselines.
Mention visual debugging.

For example, the post could describe a screen with a spacing issue. It could describe how to isolate the widget causing the problem, inspect it with guidelines and baselines, then figure out where the unwanted spacing is coming from.

Resources:

• Flutter docs on visual debugging