Remove ChainIterable usages from quick documentation and replace with HtmlChunk/HtmlBuilder.
I18ize some fragments.
GitOrigin-RevId: c9b1197efcb17de92361426759a7840ee1be8e4b
PY-33341: Now we render the “Attributes” section in the class documentation, it also allows to describe inherited attributes. (Previously we didn’t render it at all)
PY-56416: In the attribute documentation popup we are able to render attribute description from class docstring. (Previously we took documentation only explicitly from attribute one-line docstring)
PY-33341: We render the “Parameters” section in the class documentation for init parameters, described in the class docstring. (Previously user couldn't use class docstring to describe init parameters)
PY-28900: For the init parameter documentation we take the description from the class docstring if init doesn't have its own docstring. (Previously we took parameter description only from init docstring)
GitOrigin-RevId: d67bf49c72cf7a3634805a6e310c943f1ea848d1
