Show parse errors for numbers and objects; style range input

[tmeasday]

Following on from #14579 -- some UI changes @domyen wanted to make that aren't crucial to the core feature (so we won't hold up merging).

• Show errors (not just red borders) on invalid inputs for Number and Object.
• Style the Range input w/ green bar.

[domyen]

✅ Styled the range input in this commit 6d61470

I need some help with printing the error for Number and Object in the relevant stories. I can get an error to render, but only after I change the input value.

For example: I see this

But not when I initially navigate to the Number:mistyped or Number: null story. Same with the Object control.

[shilman]

Ta-da!! I just released https://github.com/storybookjs/storybook/releases/tag/v6.3.0-beta.14 containing PR #14973 that references this issue. Upgrade today to the @next NPM tag to try it out!

npx sb upgrade --prerelease

Closing this issue. Please re-open if you think there's still more to do.

[tmeasday]

Somehow I missed this comment @domyen. Let's sort of out the input errors in 6.4, I guess: #15158