Fixing Singup sequence FLASHING💥 (#11371)

After investiagting the different options ([see related
issue](https://github.com/twentyhq/core-team-issues/issues/660#issuecomment-2766030972))
I decided to add a "Verify Component" and a to build a custom Layout for
this route.

Reason I cannot use the default one is to have all preloaded once the
user changes website and lands on the verify route.

Reason I did not modify the DefaultLayout to match our need is that is
would require many changes in order to avoid preloading states for our
specific usecase.

Fixes https://github.com/twentyhq/core-team-issues/issues/660

---------

Co-authored-by: Charles Bochet <charles@twenty.com>

packages/twenty-front/src/modules/ui/theme/components/UserThemeProviderEffect.tsx

@@ -0,0 +1,17 @@
+import { useContext, useEffect } from 'react';
+
+import { ThemeSchemeContext } from '@/ui/theme/components/BaseThemeProvider';
+import { useSystemColorScheme } from '@/ui/theme/hooks/useSystemColorScheme';
+import { useColorScheme } from '../hooks/useColorScheme';
+
+export const UserThemeProviderEffect = () => {
+  const { colorScheme } = useColorScheme();
+  const systemColorScheme = useSystemColorScheme();
+  const setThemeScheme = useContext(ThemeSchemeContext);
+
+  useEffect(() => {
+    setThemeScheme(colorScheme === 'System' ? systemColorScheme : colorScheme);
+  }, [colorScheme, setThemeScheme, systemColorScheme]);
+
+  return <></>;
+};