docs: Add documentation for Anthropic Memory Tool

[AlanPonnachan]

Add documentation for Anthropic Memory Tool

Relevant issues

This documentation update is for the feature implemented in PR #16115

Pre-Submission checklist

Please complete all items before asking a Lite_llm maintainer to review your PR

• I have Added testing in the tests/litellm/ directory, Adding at least 1 test is a hard requirement - see details
  • N/A: This is a documentation-only change.
• I have added a screenshot of my new test passing locally
  • N/A: This is a documentation-only change.
• My PR passes all unit tests on make test-unit
• My PR's scope is as isolated as possible, it only solves 1 specific problem

Type

📖 Documentation

Changes

This PR adds documentation for the newly supported Anthropic Memory Tool, as requested by the maintainer.

The changes are made in docs/my-website/docs/providers/anthropic.md:

1. The heading for "Anthropic Hosted Tools" has been updated to include "Memory".
2. A new "Memory" tab has been added to the "Anthropic Hosted Tools" section.
3. The new documentation includes:
   • An :::info block explaining that LiteLLM automatically adds the required beta header for this feature.
   • A code example showing how to use the memory tool with the LiteLLM SDK.
   • A code example showing how to use the memory tool with the LiteLLM Proxy.

[vercel]

@AlanPonnachan is attempting to deploy a commit to the CLERKIEAI Team on Vercel.

A member of the Team first needs to authorize it.

[ishaan-jaff]

lgtm