Feature: Implements GitHub Notifications Management Functionality

[rmottanet]

This pull request introduces two new functions, gh-notifications-list.sh and gh-notifications-delete.sh, to allow authenticated users to view and manage their GitHub notifications directly within the tool. These utilities utilize the GitHub API to fetch and modify notification data.

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Scripts Implemented:

• gh-notifications-list.sh: This function retrieves and displays the authenticated user's current GitHub notifications. It interacts with the GitHub API (api.github.com/notifications), stores the JSON response in a temporary file, and presents the list to the user in the terminal using less for easy navigation. This is analogous to the gh-repo-list.sh implementation.

• gh-notifications-delete.sh: This function allows the user to delete (mark as read/done) a specific GitHub notification thread. It accepts the notification thread ID as a required argument and sends a DELETE request to the GitHub API (api.github.com/notifications/threads/{thread_id}) to dismiss the notification.

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Motivation:

This enhancement provides users with a convenient command-line interface to keep track of and manage their GitHub activity without leaving the terminal environment.

• Efficiency: Users can quickly check for new activity and clear out notifications without switching contexts to a web browser.
• Automation Building Block: The functions serve as foundational tools for future scripting and automation, such as creating routines to process or archive specific types of notifications programmatically.