* Add additional form validation examples
Fixes#24811.
This adds .valid-feedback to our custom styles and server side examples; previously we ommitted this to suggest you don't always need valid feedback. In addition, this adds examples of the .{valid|invalid}-tooltip classes with a new subsection in the Validation docs.
* Update validation tooltip styles to remove fixed width; instead should retain itself to the parent element
* update ids
* finish docs paragraph, mention position: relative