feat: export mem0 as tools for Vercel AI SDK

[caffeinum]

Description

mem0 + vercel AI SDK integration is nice, but even easier way would be to import it as a tool directly for AI to call as needed, instead of calling on each message manually.

This PR is a draft implementation that creates tools user can import directly into Vercel AI SDK.

Usage example:

    const memoryTools = {
      addMemory: addMemoryTool,
      searchMemory: searchMemoryTool,
      getMemory: getMemoryTool,
      deleteMemory: deleteMemoryTool,
    };

    const response = await generateText({
      maxTokens: 1024,
      temperature: 0.8,
      model: model,

      maxSteps: 4, // needed so agent can add more text after getting tool response

      tools: memoryTools,

    })

Type of change

Please delete options that are not relevant.

• [ ] Bug fix (non-breaking change which fixes an issue)
• [x] New feature (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to not work as expected)
• [ ] Refactor (does not change functionality, e.g. code style improvements, linting)
• [ ] Documentation update

How Has This Been Tested?

Tested happy-flow

• [ ] Unit Test
• [ ] Test Script (please provide)

Checklist:

• [ ] My code follows the style guidelines of this project
• [x] I have performed a self-review of my own code
• [ ] I have commented my code, particularly in hard-to-understand areas
• [ ] I have made corresponding changes to the documentation
• [ ] My changes generate no new warnings
• [ ] I have added tests that prove my fix is effective or that my feature works
• [ ] New and existing unit tests pass locally with my changes
• [ ] Any dependent changes have been merged and published in downstream modules
• [ ] I have checked my code and corrected any misspellings

Maintainer Checklist

• [ ] closes #xxxx (Replace xxxx with the GitHub issue number)
• [ ] Made sure Checks passed

[CLAassistant]

All committers have signed the CLA.