Add Optional Dependencies to Reduce Package Bloat

Fixes traceloop#2803

This PR implements optional dependencies to allow users to install only the packages they need, rather than installing all dependencies at once.

Changes Made

1. Modified pyproject.toml to:

   • Add the [tool.poetry.extras] section with optional dependencies
   • Group dependencies logically (LLM providers, frameworks, vector DBs, etc.)
   • Add convenience groups (llm-providers, frameworks, vector-dbs, general)
   • Create a full option to maintain backward compatibility

2. Updated README.md to document the new installation options with examples

Testing Done

• Verified that pip install traceloop-sdk installs only core dependencies
• Verified that pip install traceloop-sdk[openai] installs only OpenAI-related dependencies
• Verified that pip install traceloop-sdk[full] installs all dependencies (matching previous behavior)

Additional Notes

• This change maintains backward compatibility via the [full] option
• Users can now install exactly what they need, reducing package bloat
• Installation documentation has been updated to reflect these changes

Checklist

• I have followed the contribution guidelines
• My code follows the style guidelines of the project
• I have tested my changes
• I have updated documentation accordingly