Vite + TypeScript (#836)

Resolves #803

This is an initial commit to allow migrating to typescript bit by bit.
It introduces vite.
It removes all the webpack configuration (which I have no clue what all
the profiling are needed for, and couldn't find anything in the readme).
It also changes a single file from javascript to typescript:
`urlopen.js` -> `urlopen.ts`
Which was done manually, later on I'll see if I can automate most of the
migration.
For now, everything seems to work as expected.
I also upgrades storybook to use vite and renames the stories to jsx (I
honestly don't know why this complexity is needed here, but I'll keep it
for now).

cc: @damianstasik

src/components/Modal.jsx

@@ -27,9 +27,9 @@ export default class Modal extends React.Component {
       document.activeElement.blur();
     }
 
-    setImmediate(() => {
+    setTimeout(() => {
       this.props.onOpenToggle(false);
-    });
+    }, 0);
   }
 
   render() {