Create GitHub Copilot setup steps and VS Code configuration

[Copilot]

This PR adds comprehensive GitHub Copilot setup documentation and VS Code configuration to help developers get the most out of Copilot when working on the U-Report Django project.

Added Files:

• COPILOT_SETUP.md - Complete setup guide covering:
  • GitHub Copilot installation and authentication
  • VS Code configuration for optimal Django development
  • Project-specific tips for models, views, templates, and API development
  • Best practices for using Copilot with this codebase
• .vscode/settings.json - Optimized settings for Django + Copilot development
• .vscode/extensions.json - Recommended extensions for enhanced experience
• .vscode/launch.json - Debug configurations for Django development
• .vscode/tasks.json - Common development tasks (server, tests, migrations, etc.)
• test_copilot_setup.py - Validation script to verify setup completeness

Modified Files:

• README.md - Added reference to the Copilot setup guide
• .gitignore - Updated to track VS Code project configuration while ignoring user-specific settings

Key Features:

• Complete setup instructions for GitHub Copilot authentication and configuration
• Django-specific guidance for effective code generation with models, serializers, views, and templates
• VS Code optimization with proper Python interpreter, formatting (Black), linting (Ruff), and Django template support
• Project-aware settings for Tailwind CSS, file associations, and code formatting
• Development workflow integration with pre-configured tasks and debug configurations
• Validation script to ensure all tools and configurations are working correctly

The setup guide includes practical examples of how to use Copilot effectively with this Django REST Framework project, including patterns for API development, test creation, and working with the existing codebase structure.

Fixes #1278.

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💡 You can make Copilot smarter by setting up custom instructions, customizing its development environment and configuring Model Context Protocol (MCP) servers. Learn more Copilot coding agent tips in the docs.

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 83.93%. Comparing base (40ca981) to head (0cf72e0).

Additional details and impacted files

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  Coverage   83.93%   83.93%           
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  Files          48       48           
  Lines        5877     5877           
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  Hits         4933     4933           
  Misses        944      944           

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