✨(backend) add subrequest auth view for collaboration server

We need to improve security on the access to The collaboration server
We can use the same pattern as for media files leveraging the nginx
subrequest feature.

env.d/development/common.dist

@@ -53,7 +53,8 @@ AI_API_KEY=password
 AI_MODEL=llama
 
 # Collaboration
-COLLABORATION_WS_URL=ws://localhost:4444
+COLLABORATION_SERVER_SECRET=my-secret
+COLLABORATION_WS_URL=ws://localhost:8083/collaboration/ws
 
 # Frontend
 FRONTEND_THEME=dsfr