Markdown for docstrings

[hemidactylus]

Addresses #161.

[Copilot]

Pull Request Overview

This PR converts docstring markup from reStructuredText (RST) to Markdown format across multiple files in the langchain-astradb library. The changes improve documentation consistency and readability by using more modern Markdown syntax.

Key changes:

• Replaced RST code blocks (.. code-block::) with Markdown code fences (```language)
• Converted RST inline code (`text`) to Markdown inline code (`text`)
• Changed RST hyperlinks (\text `_) to Markdown links (text`)

Reviewed Changes

Copilot reviewed 7 out of 8 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
libs/astradb/langchain_astradb/vectorstores.py	Converted extensive RST formatting to Markdown in docstrings, including code examples, inline code references, and hyperlinks
libs/astradb/langchain_astradb/utils/vector_store_codecs.py	Updated inline code references from RST to Markdown
libs/astradb/langchain_astradb/utils/astradb.py	Updated inline code references from RST to Markdown
libs/astradb/langchain_astradb/storage.py	Converted JSON code blocks and inline code from RST to Markdown
libs/astradb/langchain_astradb/document_loaders.py	Updated inline code reference from RST to Markdown
libs/astradb/langchain_astradb/chat_message_histories.py	Updated inline code reference from RST to Markdown
libs/astradb/langchain_astradb/cache.py	Updated inline code references from RST to Markdown

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[Copilot]

Pull Request Overview

Copilot reviewed 7 out of 8 changed files in this pull request and generated 4 comments.

---

_{Tip: Customize your code reviews with copilot-instructions.md. Create the file or learn how to get started.}