Enhance VoiceChatBot with Greetings, Commands, Logging, and Improved UX

[annuaicoder]

This PR introduces several minor but impactful improvements to the existing VoiceChatBot:

✅ New Features

Startup Greeting

Bot now greets the user with a randomized friendly message when launched.

Basic Command Handling

Recognizes simple commands like:

"time" → announces the current time

"joke" → tells a random pre-defined joke

Conversation Logging

All user inputs and bot responses are logged to chat_log.txt for later review.

Randomized Greetings

Adds variation to bot greetings to make interactions feel more natural.

Graceful Fallback

Provides a polite response if speech recognition fails or the bot cannot generate an answer.

User Feedback in Console

Prints recognized speech to the console for clarity during interaction.

⚡ Improvements

Minor UX enhancements for smoother interaction.

Maintains full compatibility with macOS (say) and Linux (festival) TTS.

🛠 Next Steps / Suggestions

Add wake word detection (“Hey bot”) to prevent continuous listening.

Integrate more advanced TTS for natural-sounding speech.

Consider context-aware multi-turn conversation with memory.

[gunthercox]

This appears to be too many extraneous changes for what is intended to be a simple example. I would prefer to keep the code here minimal to showcase how to implement speech recognition, rather then communication features.