refactor: use EventEmitter or EventTarget

[justinmk3]

Problem

We have code that is reimplementing the EventEmitter concept: https://github.com/aws/language-servers/blob/e983bfe116c1d77460a6a932b6bbd8345b46a6a0/server/aws-lsp-codewhisperer/src/shared/amazonQServiceManager/BaseAmazonQServiceManager.ts#L148-L161

Expected behavior

replace all such code with EventEmitter or EventTarget (web compatible)