Fix css applying for root not found (#47992)
### What
This issue is introduced in #47688, we need to do the same work for
rendering single component which collecting the assets and then render
with root layout + root not found
Fix #47970
Related #47862 (partially fix the css issue but not link issue)
### How
This PR encapsulates the preload and stylesheets assets collection and
rendering process, and move them into a helper, and share between the
component rendering and the root not found rendering
