CDP Love: Improve Hog overview

[daniloc]

The notice box warns against confusing hog and hogql, only for us to immediately describe them as syntax-compatible. As a dev, that's confusing to me.
That same "Quickstart" section is almost exclusively about the limitations of hog imposed by this compatibility, and is the topline of the page - we should be giving a code example and brief explanation first (something like grabbing the webhook template, annotate it with comments, and then walk through whats happening below). The first real thing (that isn't fluff) we say about hog to most users is how weird and constrained by SQL-like syntax it is!!!! Crazy!!!
From that section, we immediately go into a syntax explanation - again, still no full-destination example! What will my hog code look like!
The "why hog" section should be a separate page entirely, it's shoved at the bottom (after a giant list of the STL functions, with no actual docs for each function!!). Sure, we link to it at the top, but it deserves its own page (or a blog post, really, so long as we can reliably link to it).
That giant list of STL functions should have real docs! We just point at the python init, which is really not good enough.
As a dev reading these docs, I'm confused. Does hog have real types? What are they? Why can toUUID take any and always successfully return a UUID? Is UUID a special hog type, like String or Tuple? These are questions the docs should preempt

PostHog/posthog#25566

[bijanbwb]

Here's my attempt at turning all the feedback above into an actionable list:

• Clean up intro about compatibility between Hog and HogQL.
• Quickstart should provide a quick code example and brief explanation.
  • something like grabbing the webhook template, annotate it with comments, and then walk through whats happening.
• Quickstart shouldn't be about limitations and constraints
• Syntax section should come after example above.
  • The giant list of STL functions should have real docs! We just point at the python init, which is really not good enough.
• Move "Why hog" section to a separate page. Should maybe also be a blog post?
• Make the docs less confusing.
  • Does hog have real types? What are they?
  • Why can toUUID take any and always successfully return a UUID?
  • Is UUID a special hog type, like String or Tuple?