Add comprehensive Copilot coding agent instructions

[Copilot]

This PR adds a comprehensive .github/copilot-instructions.md file to onboard the repository to GitHub Copilot coding agents. The instructions provide everything a coding agent needs to work efficiently with the Devtron Dashboard codebase without extensive exploration.

What's included

Project Overview & Technology Stack

• React 17.0.2 frontend with TypeScript and Vite build system
• Yarn 4.9.2 package manager with Node.js v22 runtime
• ESLint (Airbnb config) + Prettier code quality tools

Build Commands & Validation

• Complete command reference with timing: yarn install (49s), yarn build (56s), yarn lint (3s)
• Build variants for different environments (production, k8s, light builds)
• Pre-commit hooks and GitHub CI workflow details

Project Structure & Architecture

• Source code organization (src/Pages/, src/components/, src/services/)
• TypeScript path aliases for clean imports (@Components/*, @Pages/*, etc.)
• Key configuration files and their purposes

Quality Gates & Best Practices

• Husky pre-commit hooks running TypeScript compilation and linting
• GitHub CI workflow enforcing 0 ESLint warnings
• Code organization rules and CSS guidelines (BEM methodology)

Troubleshooting Guide

• Common build failures and memory issues
• Development server problems and proxy configuration
• Linting failures and import organization rules

Benefits for coding agents

• Reduced exploration time: No need to search for build commands or project structure
• Fewer failures: Clear validation steps and common error solutions
• Better code quality: Explicit standards and best practices
• Faster onboarding: Complete context in under 2 pages (1,222 words)

The instructions were validated by testing all documented commands and build processes to ensure accuracy.

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[github-actions]

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[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud