docs: improve autogenerated API docs

[barjin]

• Reapplies the changes from docs: add Google-style docstring parser from SDK (renders commented function arguments)

• Renders the object attributes (from the class docstring)

• Documents class inheritance properly now
  

• Renders inherited symbols (e.g. BasicCrawler symbols in HttpCrawler)

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Missing:

• Unpack[], union types and similar -> we might need griffe to parse the code better, pydoc-markdown stops at the return type "name", doesn't parse the syntax.
• Validation against the linked issue, see whether there's anything else missing

Related to #324

[vdusek]

I tried to render it locally. Great progress.