How to enable the webui and interact with the Flexget daemon?

Looking at the template the webui requirements seem included, but the webui fails to start for me:

2023-04-14 07:28:28 CRITICAL webui Failed to start web ui, this can happen if you are running from GitHub version and forgot to run the web ui build, see for instructions

From their website:

If you are running flexget from git, you can run python bundle-webui to get the latest release of webui.

I cannot find these in Nixpkgs. I understand that I can fetch them from Pypi with some additional configuration, but before I resort to that I wanted to make sure it is actually necessary; is the webui requirements not included in the Nixpkgs build of Flexget?

I’m also wondering whether it is possible to authorize Trakt, which require interacting with the daemon? There doesn’t seem to be a relevant NixOS option and manual interaction with the cli attempts to spawn another daemon instead of interacting with the existing one; is Trakt authorization currently impossible due to the nature of NixOS?