Add ESLint configuration and upgrade development tools

[Copilot]

This PR modernizes the development tooling by adding ESLint configuration and upgrading the existing prettier setup, along with implementing comprehensive npm scripts for code quality checks.

Changes Made

New Dependencies

• Added @electerious/eslint-config@^5.2.0 - Provides consistent ESLint rules
• Added eslint@^9.34.0 - Core ESLint functionality
• Upgraded @electerious/prettier-config from ^3.0.0 to ^4.0.0

Configuration Files

• Created eslint.config.js - Exports the Electerious ESLint configuration

Updated npm Scripts

Replaced and added scripts for comprehensive code quality workflow:

{
  "eslint": "eslint \"**/*.js\"",
  "format": "npm run eslint -- --fix && npm run prettier -- --write", 
  "lint": "npm run eslint && npm run prettier -- --check",
  "prettier": "prettier --ignore-path .gitignore \"**/*.{js,json,md,yml}\"",
  "test": "npm run lint && node --test"
}

The start script was preserved as requested.

Code Quality Improvements

Applied ESLint auto-fixes and manual corrections to resolve:

• Prefer Node.js built-in modules (node:http, node:crypto, etc.)
• Use Number.isNaN() over global isNaN()
• Fix regex escaping issues
• Add missing switch statement default cases
• Remove unused variables and functions
• Improve variable destructuring patterns
• Replace process.exit() with proper error throwing

Compatibility Fixes

• Replaced Promise.withResolvers() with manual Promise construction for Node.js v20 compatibility
• Fixed variable declaration patterns to follow ESLint rules

Workflow Impact

The new scripts provide a complete development workflow:

• npm run lint - Checks code style and quality without making changes
• npm run format - Automatically fixes all auto-fixable issues
• npm test - Runs linting + prettier checks + Node.js tests
• npm run eslint - Runs only ESLint checks
• npm run prettier - Runs only Prettier checks

All scripts now pass successfully, ensuring consistent code quality across the project.

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