feat: update team analytics module

Description

Added a cache-safe Team Analytics module to aggregate team-level statistics including commits, merge requests, issues, projects, and groups.

Includes:

• Aggregated team commit, MR, issue, project, and group data
• Member-wise contribution counts
• Date range filtering utility
• Team-level statistics summary calculation
• Proper timezone handling (Asia/Kolkata)

Designed with modular structure and clean separation of concerns to support scalable team analytics features.