[FS router] add options to enable Spring Security

[krissvaa]

Todo:

• Add roles allowed to client and server-side
• Add access checks for hilla views by view metadata (roles allowed)
• Add Hilla public routes as anonymous allowed to VaadinWebSecurity
• Apply access checks as soon as routes are available on server side
• Add tests and documentation/examples.

For client-side access control - existing implementation should still work (as both are needed for complete access control implementation in Hilla)

[platosha]

Let's address the main layout menu filtering as a separate issue.

[vaadin-bot]

This ticket/PR has been released with Hilla 24.4.0.alpha11 and is also targeting the upcoming stable 24.4.0 version.