Do action matching in plugin server

[Twixes]

If we match fully processed events to actions in the plugin server (in parallel with saving the event to DB), we'll be able to again have asynchronous events>actions matching. Even more importantly, we'll be able to support method onAction(action: Action, event: PluginEvent) on plugins, facilitating making webhooks a plugin. In the long run something like PostHog/posthog#3357 may be built on top of this.

[mariusandra]

How much effort will this be? I guess we need the entire filtering logic (that is probably already implemented twice in django? Once for postgres and once for clickhouse?)... into JS. Sounds like a lot of meticulous work...

[Twixes]

The logic is actually common, because we perform matching on a temporary event created in Postgres (as storing action definitions in ClickHouse is a pain).

[Twixes]

Superseded by #235 I suppose. It's the same idea, but fleshed out more in the newer issue.