feat: Create Financial Assistant agent with Docker and API

[dbarenas]

This commit introduces the "Financial Assistant" agent, forked from the "Financial Advisor" agent.

Key changes include:

• Created a new agent directory: python/agents/financial-assistant/.
• Updated README.md with:
  • New agent name and description.
  • Instructions for running with Docker (Dockerfile created).
  • Information on API usage (FastAPI app created).
  • Details on model customization and limitations.
• Added a Dockerfile for containerized execution.
• Implemented an API using FastAPI:
  • Added fastapi and uvicorn to pyproject.toml.
  • Created financial_advisor/main.py with a /invoke endpoint.
  • Updated Dockerfile CMD to run Uvicorn.

Challenges Encountered:
The primary challenge was with building the Docker image due to issues with poetry lock and poetry install in the provided environment. The poetry lock command consistently failed with a "Could not parse version constraint: ==*" error when processing the full set of project dependencies for Poetry version 1.7.1.

Attempts to resolve this included:

• Ensuring the project name in pyproject.toml was correct ("financial-assistant").
• Trying various poetry lock and poetry install strategies.
• Modifying the Dockerfile to use poetry export to a requirements.txt and then pip install -r requirements.txt.

Unfortunately, the poetry export command also relies on a valid lock file for full dependency resolution, so I could not fully overcome these issues in the current environment. I was unable to successfully complete testing the Dockerized agent due to these persistent Docker build failures related to Poetry.

Further work would require a more flexible environment for Poetry or manual adjustments to the dependency list to isolate the problematic constraint. The current submission includes all code changes up to the point of the Docker build issues.

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