Added button and beginning of setup screen

src/components/Button.tsx

@@ -0,0 +1,27 @@
+import type { ReactNode } from 'react';
+
+import './Button.css';
+
+export interface ButtonProps {
+  type?: 'primary' | 'secondary';
+  href?: string;
+  children?: ReactNode;
+  onClick?: () => void;
+  full?: boolean;
+  className?: string;
+}
+
+export function Button(props: ButtonProps) {
+  const classes = `button button-${props.type ?? 'primary'} ${props.className ?? ''} ${props.full ? 'full' : ''}`;
+  if (props.href)
+    return (
+      <a href={props.href} className={classes} target="_blank" rel="noreferrer">
+        {props.children}
+      </a>
+    );
+  return (
+    <button className={classes} type="button" onClick={props.onClick}>
+      {props.children}
+    </button>
+  );
+}