feat: add email summary agent

[ronantakizawa]

An AI-powered agent that collects all emails received throughout the day and sends you a comprehensive daily summary using the OpenAI API.

Features

• Automatic Email Collection: Stores all emails received in your AgentMail inbox
• AI-Powered Summaries: Uses OpenAI API to generate intelligent, categorized summaries
• Daily Schedule: Sends summaries at a configurable time each day
• Smart Categorization: Groups emails by type (urgent, meetings, requests, etc.)
• Action Items: Highlights deadlines and tasks that need attention
• Acknowledgment Messages: Optionally sends auto-replies to senders
• Test Data: Includes 12 sample emails for testing

How It Works

1. Emails arrive at summary-agent@agentmail.to throughout the day
2. At scheduled time (default 5 PM), agent fetches all emails from inbox
3. AI analyzes all emails and generates a categorized summary
4. Summary email sent to your configured address