docs: various improvements to Python API tutorial

[agilgur5]

Summary

Several documentation improvements to the Python API tutorial

Originally started to fix the same note as #187, but noticed several other improvements that could be made

Details

• additions:

  • add link to the Python API reference
  • add link to the FAQ for getting API keys

• stylistic improvements:

  • simplifications:
    • "databases are databases" is redundant
    • "default configuration is applied by default" is redundant
    • also remove redundant words like "that"; state directly instead
    • see also k8s style guide on direct language (which I use and reference often for docs -- it's a pretty great style guide!)
  • remove duplications:
    • remove duplicate "learn more" configuration link
    • remove duplicate note on the demo assistant
  • consistency + parallelism:
    • use same formatting for Vector DB choices as LLM choices
      • i.e. bold + code backticks
    • for demo helpers, consistently use "Not x. Instead y. It provides a quick way [...]"
      • previously this had a few different formats, different conjunctions, etc
      • parallelism & consistency makes this easier to understand
  • code style:
    • remove new line after !!! note
      • otherwise most markdown editors will recognize the block as a code block due to the 4 space indentation
      • EDIT: reverted due to prettier per review comments, c.f. docs: small improvements to "Set Configuration" how-to #197 (review)

• fix various spelling and grammar errors and typos:

  • "it's" -> "its"
    • "it's" = "it is", "its" = possessive
  • no comma needed after "And"
  • comma splice in "vector database, and similar" -> split into two sentences
  • comma splice in "actual database, but" -> split into two sentences
  • "databases at can" -> "databases that can"
  • "in as objects" -> "as objects"
  • "You select the" -> "Select the"

[pmeier]

Just one minor comment. I let @pavithraes handle the rest.

[pmeier]

See #197 (review).

[pmeier]

Aaaand of course I forgot the most important part: hello @agilgur5 and welcome to the project 👋 Thanks a ton for taking the time to fix our docs. Really appreciate that!

Redering issue addressed

[pavithraes]

Thank you so much, @agilgur5! All your changes look good to me. I've added a minor formatting suggestion flagged by the linter, we can merge after this. :)

[pmeier]

Thanks again @agilgur5!

@pavithraes for the future: if there is nothing left other than auto-formatting, it is usually faster to just pull the PR, apply the formatting and push it again instead of waiting yet another round of the review-fix-cycle. If you don't want that, feel free to just comment something along the lines of "please apply the auto formatting so we can merge". No need to flag all instances when CI is doing the same.