Add an Admin Moderation Queue

[Abd-Standard]

Description:
Create a centralized interface where administrators can review pending grant submissions, updates, and user reports.

Acceptance Criteria:

Pending items are displayed in one location.
Administrators can approve or reject submissions.
Moderation actions update the relevant record

[smartalee]

I would like to take this pls

[grantfox-oss]

🦊 GrantFox — @smartalee has been assigned to this issue as part of the Third Campaign campaign!

Next steps:

1. Open a Pull Request referencing this issue (e.g., Closes #159)
2. Your PR will be reviewed by the Core-Foundry maintainers

Good luck! Track your progress on GrantFox.