Modernization with TypeScript and Event Target

[compulim]

Changelog

Please copy and paste new entries from CHANGELOG.md here.

Changed

• 💥 Modernized some code with TypeScript, more type-aligned to W3C Speech API, and moved to official Event Target API, in PR #220
  • SpeechRecognitionResult and SpeechRecognitionResultList is now a array-like object, use Array.from() to convert them into an array

Design

We are moving slowly. The core createSpeechRecognitionPolyfill is still JS with /** @type {...} */ type annotation, instead of fully TypeScript.

Specific changes

Please list each individual specific change in this pull request.

• Upgraded SpeechRecognition from event-target-shim to official EventTarget API
• Typed out SpeechRecognitionEvent and related classes
• More property getter than variable