ghai: advancements to the gh command

ghai-my-issues: My preferred output for browsing issues. Clean and easy to navigate from the terminal.

ghai-process-notifications: AI-powered notification processor that uses policies to automatically decide whether GitHub notifications should be marked as read or kept unread. Features comment tracking since last read, customizable decision policies, and a --mark-read-by-default option.

Example Notification Policy

The notification processor uses policy files to make decisions. Here's an example policy:

If the issue or pull request was closed after it was last read or it was never read, output {"action": "mark-unread"}
If the issue or pull request has a comment after it was last read, output {"action": "mark-unread"}
If the issue or pull request has no comments, output {"action": "mark-read"}
If the issue or pull request is somehow associated with @rescrv, output {"action": "mark-unread"}

This policy keeps notifications unread for recently closed items, items with new comments, items with no comments at all, and items associated with @rescrv, while marking everything else as read.