Repository overview with commit list and branch graph

### Description

Add a repository overview that shows a branch graph and a list of all commits, similar to e.g. Atlassian Sourcetree.

### Use case/motivation

I'm mostly using the command line for Git but I also have Sourcetree running all the time for the nice visual overview it provides, listing all commits next to a branch graph. It would be great if NB provided that same overview since it already has lots of other Git/Team features.

### Related issues

_No response_

### Are you willing to submit a pull request?

No

No files, tests, or entry points are named. Start by locating NetBeans' existing Git and Team features, then define the repository overview's scope and UI behavior. Done means a repository view lists all commits alongside a branch graph comparable to the requested Sourcetree overview.

Written by the indexing model from the issue text.