Support new reference docs syntax

[mdrxy]

Hello!

We have switched from using Sphinx/reStructuredText to Material for MkDocs, which is a Markdown-based syntax. Consequently, the inline docstrings and reference docs in the langchain-parallel repo need to be updated accordingly.

Please update the following:

• .. code-block:: {LANGUAGE} admonitions should be translated to standard Markdown codeblocks, e.g.:

  ```language
  some code
  ```
  

• URLs with the format `Text to hyperlink <https://link.com>\`__ or `Text to hyperlink <https://link.com>\`_ should be replaced with markdown links like [Text to hyperlink](https://link.com)

• Double-backtick inline code like ``inline code`` should be replaced with single backticks like `inline code`

• Callout admonitions:

  • .. warning::, .. important::, and .. note:: should be updated to !!! warning "Optional title", !!! important, and !!! note respectively. (each can have an optional title). See docs.
  • Dropdowns like .. dropdown:: {TITLE} should be replaced with callouts and the ??? syntax. See docs.

• .. versionchanged:: x.y.z should be translated to !!! warning "Behavior changed in x.y.z" (with optional descriptions)

• .. versionadded:: x.y.z should be translated to !!! version-added "Added in version x.y.z" (with optional descriptions)

• .. deprecated:: x.y.z should be translated to !!! deprecated

• :private: directives should be removed. New reference docs will automatically exclude methods prefixed with a single underscore, e.g. _function()

  • If there are functions that do not use this syntax or can not be updated to use it, we are able to filter out functions by name. Reach out and I can help.

• Any cross references with :func:, :class:, or :meth: should be updated to use Markdown links, e.g.: [Runtime][langgraph.runtime.Runtime]

[mdrxy]

Example of issue: