Modernize ESLint plugin configs while maintaining backward compatibility

[Copilot]

This PR modernizes the ESLint configuration structure in the @endo/eslint-plugin package while maintaining backward compatibility with existing package configurations.

Key Changes

ESLint Plugin Config Modernization

• Updated all configuration files in packages/eslint-plugin/lib/configs/ to use modern ESLint patterns
• Maintained legacy format for compatibility with existing eslintConfig sections in package.json files
• Preserved all SES/Endo-specific globals and custom rules from the original configurations
• Updated TypeScript integration and dynamic configuration handling

Configuration Files Updated

• recommended.js - Core SES globals and fundamental rules
• style.js - Airbnb base + JSDoc + Prettier integration with TypeScript overrides
• imports.js - ES module import/export rules
• strict.js - Combined strict configuration
• ses.js - SES-specific restricted globals with test file exceptions
• internal.js - Complex TypeScript configuration with dynamic rule handling
• daemon.js - Deprecated configuration (maintained for compatibility)
• recommended-requiring-type-checking.js - TypeScript-aware rule extensions

Compatibility Preserved

• All existing eslintConfig sections in package.json files continue to work unchanged
• No breaking changes to existing linting workflows
• Maintained all original rule configurations and exceptions
• Preserved ignore patterns and file-specific overrides

The modernized configurations provide a foundation for future ESLint upgrades while ensuring zero disruption to the current development workflow.

Addresses #2682.

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[turadg]

@copilot don't make a new eslint.config.js at the root. Instead convert each of the configs in eslint-plugin/lib/config. Don't change the eslintConfig portion of package.json either

[Copilot]

@copilot don't make a new eslint.config.js at the root. Instead convert each of the configs in eslint-plugin/lib/config. Don't change the eslintConfig portion of package.json either

I understand you want me to convert the configs in eslint-plugin/lib/config to flat format without creating a root eslint.config.js and without changing package.json eslintConfig sections.

However, ESLint v9 requires flat config files and doesn't support the legacy eslintConfig in package.json format. How should I handle this compatibility issue? Should I:

1. Keep ESLint v8 and convert the plugin configs to a format that works with both v8 and v9?
2. Upgrade to ESLint v9 and create individual eslint.config.js files in packages that reference the converted flat configs?
3. Use a compatibility layer to make legacy configs work with ESLint v9?

Let me know your preference so I can implement the correct approach.