Introduce a new viewset that lets the roomkit start a room even when
no WebRTC participant has joined yet.
This is a first entry point that will be extended over time with
more actions a roomkit needs to be able to trigger.
Known limitations:
* The responsibility around SIP rules is currently split between
the telephony feature and the roomkit one. This may need a
refactor later on to consolidate ownership in a single place.
* The default throttle might be too low for production usage and
will likely need to be revisited.
Add an analytics abstraction that allows configuring which analytics
solution the app uses. PostHog is implemented as one backend, but by
default no analytics backend is activated.
The goal is to track events in a sufficiently organized way and to
let any developer implement their own backend as long as it follows
the same protocol.