Reorganize folder structure and use snake_case

[cube-logic]

Is your feature request related to a problem? Please describe.
reorganizing folders structure and making the addon easy to navigate

Describe the solution you'd like
Godot from what I've seen has changed conventions from godot 3 to mostly snake_case and I don't see the project utilizing this
https://docs.godotengine.org/en/stable/tutorials/best_practices/project_organization.html
Also I've tried debugging some bugs I had with it that are already open in git, there is a test project outside of the folder and also inside, duno what they're for

Describe alternatives you've considered
For the beta I would suggest to keep just the required files for the addon to function in a simple structure with snake_case folder names and script names that are consistant
And also keep all of the examples assets in the base directory and not inside the addon directory

[CakeVR]

Hello, thanks for opening an issue about consistency.

The Tests folder is explained on the README.md: https://github.com/dialogic-godot/dialogic?tab=readme-ov-file#testing

While you are correct and we like to stick to the guidelines, the damage is done already. It may cause huge breaking changes with how fragile Godot can be. We would have to analyse how much trouble this will push onto our current users.

We are still in Alpha, about to go Beta, it may still fundamentally break all projects.