Update dependencies and fix security vulnerabilities

[buge]

Updated project dependencies to their latest stable versions, addressing security vulnerabilities and ensuring compatibility.

Key changes include:

• Migrating ESLint configuration to the new flat config format (eslint.config.js).
• Updating TypeScript, Prettier, Mocha, and other dev dependencies.
• Pinning chai to version 4 to maintain compatibility with the CommonJS environment.
• Fixing linting issues in test files (test/time_test.ts and test/unit_test.ts) that were flagged by the updated linter.
• Resolving npm audit findings.

All tests passed successfully (npm test) and the project builds without errors (npm run build).

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PR created automatically by Jules for task 5226221478310357354 started by @buge

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