Give dashboards a themed orb background and a solid current-nav state.

Login pages share the same wash as the app shell; customer light mode matches business while dark mode stays gray.

Co-authored-by: Cursor <cursoragent@cursor.com>

apps/business/src/components/BackgroundOrbs.tsx

@@ -0,0 +1,12 @@
+import styles from './BackgroundOrbs.module.css'
+
+export function BackgroundOrbs() {
+  return (
+    <div className={styles.bgOrbs} aria-hidden="true">
+      <div className={styles.orb1} />
+      <div className={styles.orb2} />
+      <div className={styles.orb3} />
+      <div className={styles.orb4} />
+    </div>
+  )
+}