Ability to change project entry point

### What problem are you trying to solve?

Using Fresh as an example, if you change your project structure, such as moving your source code into a `src/` directory, then any existing deployments will begin to fail as you cannot change / update the entrypoint path unless you re-create the project

### Describe the solution you'd like

A new input / select drop down, similar to the project creation screen, where you can select a new entrypoint for the project.

### Describe alternatives you've considered

In my case the only alternative I had found is to delete the project & re-create it. Which is fine but not ideal.

### Documentation, Adoption, Migration Strategy

_No response_