Set default project path where a project was last created

[KoBeWi]

Closes godotengine/godot-proposals#1312

[akien-mga]

See godotengine/godot-proposals#1312 (comment), I don't think this is the right approach.

[KoBeWi]

I added a checkbox:

Though it needs a better place.

Changed default path to empty string. The checkbox will be automatically enabled if the path is empty.

[KoBeWi]

As discussed on chat, I changed the path setting to be hidden.

Note that, since the setting was renamed, the old path is going to be lost when upgrading project. #114971 adds necessary compatibility methods to handle this, I can reuse them once it gets merged.

[groud]

As I mentioned in the chat, I'm in favor of making it simpler, and register the last used path all the time instead of making it an option via a checkbox. I'm in favor of a simpler UI, removing (arguably) the less useful options whenever possible.

[KoBeWi]

I'm not sure about removing the checkbox, although maybe it's less useful if the setting is not exposed 🤔