Improve branch list: visually distinguish local vs remote branches

### The feature request

It would be helpful if the branch list visually distinguished local branches from remote-tracking branches. Currently, both types of branches look identical, which makes it harder to quickly understand the state of the repository, especially in larger projects.

### Proposed solution

Use different icons for local vs remote-tracking branches (for example, a computer icon for local and the network icon for remote).

### Additional context

_No response_