Feedback for docs

[HFKKristof]

As a beginner in langfuse it's not clear for me what is the difference when using:

1. @observe() + langfuse_handler = langfuse_context.get_current_langchain_handler()
2. langfuse_handler = CallbackHandler()
   Or when should I use one over the other.

Another thing it was (is) a little bit confusing is the lot of possibilities of enriching the logs.
I mean: events, traces, spans, observations, scores, etc.
Maybe a summary page to summarize them all with a few real-life examples would be great,
to ha a clear and high-level overview about which one is best for what situation.

Other then these, it's a cool tool! Thanks!