Feat/upgrade nodejs

[suany0805]

This pull request makes significant updates to the project's linting configuration, Node.js version support, and development dependencies. The main changes include migrating from the legacy ESLint configuration to the new flat config system, updating Node.js version requirements across the project, and refreshing TypeScript and related dependencies for all example packages.

Linting and Configuration Updates:

• Migrated from the legacy .eslintrc.json and .eslintignore files to a new eslint.config.mjs using the ESLint flat config system, with updated plugin usage and modernized rule sets. This change streamlines and modernizes the linting setup. [1] [2] [3]
• Updated ignore patterns for ESLint to match the new configuration style and ensure proper exclusion of build artifacts and dependency directories.

Node.js Version Upgrades:

• Updated the required Node.js version in .nvmrc, package.json, and CI workflow to support Node.js versions 20 and above, including the latest LTS and current releases. This ensures compatibility with the latest Node.js features and security updates. [1] [2] [3]

Example Package Maintenance:

• Upgraded TypeScript and @types/node dependencies in all example packages (jest, mocha, symbolPlugin) to the latest versions for improved type safety and compatibility. [1] [2] [3]
• Added a check script to example packages to streamline compilation and testing workflows. [1] [2] [3]

Code Quality Improvements:

• Minor code cleanups in example source files, such as improving type imports and removing unnecessary comments. [1] [2] [3] [4]