Add script to setup team documents on firestore

[amrit110]

This pull request adds a new script, scripts/admin/setup_teams.py, which streamlines the process of creating or updating team documents in Firestore from a CSV file. The script provides validation, error handling, and a dry-run mode, making it easier and safer to manage teams in bulk.

Key features and changes:

New Team Setup Automation Script:

• Introduces setup_teams.py, a command-line tool to read team names from a CSV file and create or update corresponding documents in Firestore, including support for a dry-run mode to preview changes without making modifications.
• Implements comprehensive CSV validation, including checks for missing columns, empty or invalid team names, and duplicate entries, with user-friendly error reporting.
• Provides clear progress feedback and summary tables using the rich library, enhancing the user experience during batch operations.
• Handles Firestore interactions robustly, updating timestamps for existing teams and creating new documents for new teams, with detailed reporting of created, updated, and failed operations.
• Includes thorough documentation, usage examples, and structured output to assist administrators in managing team data efficiently.