feat: add mock LLM chatbot response function

[YedianCheng]

Summary

This PR introduces a mock version of the chatbot response function get_llm_response() to simulate LLM replies. It is part of my preparation for Google Summer of Code 2024 (GSoC) with Sugar Labs, under the proposal to enhance the Speak Activity with gen-AI capabilities.

What it does

• Adds a mock LLM response function returning randomized phrases
• Prepares the integration point for future LLM interaction and persona expression
• Ensures compatibility with current UI and facial SVG expression features

Note: This is an early mock implementation for testing purposes only. The actual LLM logic will be implemented in a separate file (similar to brain.py) in future development.

Testing

• The activity launches successfully
• Chatbot responds with expected mock responses
• No existing functionality is broken

Looking forward to feedback and happy to iterate further!

[quozl]

Thanks. Could you convert to draft?

[YedianCheng]

Thanks. Could you convert to draft?

Sure! I've converted it to a draft. Thanks for the suggestion.

[chimosky]

Why the name and bundle_id change?