Introduce favorites selection option for Instances and Devices

### Description

As part of the redesign of the FlowFuse Application Home Screen (see #3366), the introduction of a 'Favorites' selection feature for both instances and devices was proposed (see https://github.com/FlowFuse/flowfuse/issues/3152#issuecomment-1887377732) . This enhancement will enable users to mark their most relevant instances and devices as 'favorites', ensuring quick and easy access from the Home Screen.

- The selection should be per User / User based

## Design

https://github.com/FlowFuse/flowfuse/issues/3152#issuecomment-1887377732

### Which customers would this be available to

Everyone - CE/Starter/Team/Enterprise

### Have you provided an initial effort estimate for this issue?

I have provided an initial effort estimate