Add Automated Stale Issue Management GitHub Action

[Varun-S10]

PR Description:
This PR adds automation to help us manage issues. This keeps our repository organized and focused. The script acts as an automated helper, finding and resolving inactive discussions.

Why This Is Needed:

• Keeps Things Clear: It keeps our backlog clear of old, inactive issues.
• Saves Time: Reduces manual work for maintainers following up on stalled discussions.
• Clearer Communication: Helps issue creators understand when their input is needed.
• Faster Resolution: Encourages quicker responses and decisions.
• Healthy Repository: Makes it easier to find and work on active tasks.

How It Works (Main Steps):

The script follows clear rules based on issue activity and who is commenting:

1. Marking as Stale: If an issue has no activity for {stale_threshold_days} days, it will be marked with the '{STALE_LABEL_NAME}' label and receive a comment asking for an update.
2. Closing Inactive Issues: If an issue remains stale (no activity from the author or other users) for an additional {close_threshold_days} days after being marked stale, it will be automatically closed.
3. Recognizing Activity: Any new comment from the original author or another non-bot user will remove the '{STALE_LABEL_NAME}' label, making the issue active again. If someone edits the issue description without adding a comment, the script will notify maintainers so important updates aren't missed.
4. Understanding Maintainer Comments: If a maintainer's last comment is a discussion with another maintainer, the issue stays active. If a maintainer asked a question, requested more information, or gave a suggestion, and there's no response for {stale_threshold_days} days, the issue will be marked as stale and also get a '{REQUEST_CLARIFICATION_LABEL}' if it doesn't have one already. Simple status updates from maintainers keep the issue active.