Franknoirot/fix onboarding units (#366)

* Fix up camera step copy and pane opacity for step

* Fix broken onboarding redirect with double slash

* Fix pane height for web bug from blur filter
I found a bug with browser behavior, at least on Chrome.
If you use `backdrop-filter: blur()` at all, you can't
have any children that overflow. The browser will ignore
any attempt and make those children max full-height.
This broke our side panels after I added blur, but
only in Chrome/browser target.

Signed-off-by: Frank Noirot <frank@kittycad.io>

* Fix bug with unit system
Changing the unit system didn't also change the
base unit in the onboarding anymore. It needed
updated to use XState the same way as `/settings`

Signed-off-by: Frank Noirot <frank@kittycad.io>

* Fix AppHeader item spacing when there's no toolbar

---------

Signed-off-by: Frank Noirot <frank@kittycad.io>

src/components/AppHeader.tsx

@@ -28,8 +28,9 @@ export const AppHeader = ({
   return (
     <header
       className={
+        (showToolbar ? 'grid ' : 'flex justify-between ') +
         styles.header +
-        ' overlaid-panes sticky top-0 z-20 py-1 px-5 bg-chalkboard-10/70 backdrop-blur-sm dark:bg-chalkboard-100/50 dark:backdrop-blur-0 border-b dark:border-b-2 border-chalkboard-30 dark:border-chalkboard-90 items-center ' +
+        ' overlaid-panes sticky top-0 z-20 py-1 px-5 bg-chalkboard-10/70 dark:bg-chalkboard-100/50 border-b dark:border-b-2 border-chalkboard-30 dark:border-chalkboard-90 items-center ' +
         className
       }
     >