[Feature Request]: Override default settings via config

### Describe the problem I'd like the ability to customize the [default settings](https://github.com/cinnyapp/cinny/blob/8f1add6059c5efa72232d4bc060c6a5e1acb74e5/src/app/state/settings.ts#L46-L78) to make less 'technical' users feel more at home. E.g. disabling the `hideMembershipEvents`, enabling `hour24Clock` etc. ### Describe the solution you'd like To customize the default settings using the `config.json` file. ### Alternatives considered To customize the default settings using environment variables or as an admin / with specific permission using the UI. ### Additional context As a workaround you should be able to build the app yourself with default settings, but that would make updating a lot more annoying.