Improve notebook generation capabilities

[TheGupta2012]

Summary

Backend enhancements:

• Improved the system prompt for code generation to require correct, executable, and compatible Python code, especially when using multiple libraries, and to avoid deprecated or non-existent methods. The user prompt now requests "clean Python code" for clarity. [1] [2]
• Added a new generate_title_for_notebook method to automatically generate descriptive, snake-case notebook titles based on the generated code and markdown. The method ensures title uniqueness and length constraints, and integrates this into the notebook creation flow so new notebooks are named meaningfully. [1] [2]

Prompt and context improvements:

• Updated the main chat system prompt to clarify that the assistant is for qBraid JupyterLab users, and instructs the assistant to use the "qbraid-docs-search" tool when qBraid or related terms are mentioned. [1] [2]

Frontend (UI/UX) improvements:

• Implemented streaming of notebook cell content (both code and markdown) as it is generated, by progressively updating the cell's content in chunks with a short delay between updates. This provides a more interactive and responsive experience for users as they see content appear in real time. [1] [2] [3]