feat: support self hosted PostHog instances for ui_host#30

lorenzdiener wants to merge 1 commit intoceladonworks:mainceladonworks/pixiehog-app:mainfrom

lorenzdiener:27-url-settings-for-selfhosted-ph-instanceslorenzdiener/pixiehog-app:27-url-settings-for-selfhosted-ph-instancesCopy head branch name to clipboard