Add event tracking with PostHog

[rafaellehmkuhl]

This patch adds tracking of specific events to the PostHog platform.
It will help us better understand user behavior and how to improve the app.

For now, the following events are tracked:

• App start
• Session time
• Video recording start/stop
• Video recording time
• Vehicle arming/disarming

More events should be tracked in the future.
User-data is anonymized by default.

[ArturoManzoli]

Wow, this opens a lot of possibilities! Great feature to have.
Have you noticed any Cockpit performance changes when enabling this logs?

[rafaellehmkuhl]

Wow, this opens a lot of possibilities! Great feature to have. Have you noticed any Cockpit performance changes when enabling this logs?

It does indeed!

No performance changes, but I remembered I didn't check how well it behaves when the application is offline, and if the events are cached for the next session, like in Sentry. Will do some tests and if everything goes right I will merge it.

EDIT: from my tests the events are lost if the application is closed before going online. I've opened an issue in their library repo to discuss that. In the meantime I will implement the persistence on our side.

[rafaellehmkuhl]

@ArturoManzoli I've added a dedicated IndexedDB-based queue, that supports offline events. Could you check if they work for you?

You basically want to test if, while offline, some event captures fail (in the network tab) and are cached in the dedicated IndexedDB (application tab), if they are still there when you reopen Cockpit and if their network calls are correctly sent when you reopen Cockpit again while online.