feat: throwaway netbox deployment for end-to-end testing

compose stack modelled on the production netbox deployment (same pinned
images, worker, healthchecks) minus traefik: the API is served straight
on localhost and nothing survives an e2e-down.

.gitignore

@@ -9,6 +9,7 @@ __pycache__/
 
 # Configuration
 config.yaml
+e2e/.env
 
 # IDE
 .idea/