feat(cdp): Add a bunch more metrics counting for hog functions

[benjackwhite]

Problem

Starting to build up dashboards for alerting and such (see here) - lets count a bunch more things to do that

Changes

• Count invocations with their outcome
• Count async responses with their outcome
• Adds histogram observer for function timings

👉 Stay up-to-date with PostHog coding conventions for a smoother review.

Does this work well for both Cloud and self-hosted?

How did you test this code?

[posthog-bot]

Hey @benjackwhite! 👋
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