Adding the Assigined mr, assigned issues column in analytics

✨ Enhancement: Add Assigned MRs and Assigned Issues to Team Leaderboard

📌 Overview

This enhancement extends the Team Leaderboard in the GitLab Compliance & Analytics Tool by introducing two new member-level metrics:

• Assigned MRs
• Assigned Issues

These fields will track the number of Merge Requests and Issues where a user is assigned (not authored), providing better visibility into responsibility distribution and workload allocation across teams.

This is a non-breaking feature extension and does not modify any existing scoring or filtering logic.

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🎯 Objective

Enhance the Team Leaderboard to:

• Display assigned work separately from authored work
• Improve visibility into user responsibilities
• Provide better team workload analysis
• Maintain full backward compatibility

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🆕 New Fields

Each member row in the Team Leaderboard table will include:

• Assigned MRs → Count of merge requests where the user is an assignee
• Assigned Issues → Count of issues where the user is an assignee

These metrics:

• Are calculated independently from authored items
• Do not affect the scoring formula
• Respect both Date Filter and Project Filter
• Work in both normal and project-filter pipelines

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🛠️ Scope of Changes

Backend Extensions

The following functions will be extended safely:

• process_single_user()
• process_single_user_project_filtered()

New logic will:

• Fetch merge requests using assignee_id
• Fetch issues using assignee_id
• Deduplicate results where necessary
• Add two new fields to the return dictionary:
  • assigned_mrs
  • assigned_issues

Existing author-based logic remains unchanged.

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UI Updates

The Team Leaderboard table will include two new columns: