Mixar-AI/mixar-app ? reverse-engineered prompt

Build me a working local version of Mixar, basically a Blender based desktop app with the extra Mixar features wired up and runnable from source. I want the normal Blender tools to still be there, plus an in app chat assistant that can work on the scene, layer based texture painting, AI text or image to 3D generation, moodboards, scene generation, asset search, and support for using my own provider keys. Please do not try to recreate the hosted backend since that is separate, just make the desktop app authenticate and talk to the configured service endpoints from the environment settings.

Set it up the right way so the custom Mixar overlay builds on top of Blender, the app launches cleanly, and the Python parts get installed into the built app. If anything is unclear, look up the current Blender build docs and any public docs you need online. At the end, give me a simple way to launch it, plus the exact environment values I need to fill in so I can sign in and test the AI features.