🏗️ Architect: Refactor /activity command structure

[google-labs-jules]

💡 Goal: Make the /activity command more readable and maintainable by decoupling Discord API interactions (invite creation) and message formatting from the core orchestration logic.

🔨 Changes:

• Extracted _generateInviteUrl to handle Discord invite logic and benign error catching, added Type Hints and Docstring.
• Extracted _buildActivityMessage to format the string response, added Type Hints and Docstring.
• Cleaned up the main activity method body to rely on these named helpers.

🛡️ Safety: The logic is completely unchanged. Fallbacks to 'N/A' and msg formatting are identical to the original inline code.

📖 Readability: The activity method now clearly shows the steps: getOrCreateSession -> _generateInviteUrl -> _buildActivityMessage -> send(msg).

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PR created automatically by Jules for task 15431918665326841614 started by @TytaniumDev

[google-labs-jules]

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