Improve JSDoc to match code

[shadowspawn]

Pull Request

Using Typescript to check the Javascript identifies a lot of minor issues. This PR addresses most errors in the JSDoc.

(Previous abandoned #1120 also included code changes.)

Problem

JSDoc issues are displayed when check index.js with TypeScript:

npx tsc --allowJS --checkJS index.js --noEmit
...
Found 53 errors.

or by adding comment to index.js in Visual Studio Code:

// @ts-check

Solution

Make minor changes to the JSDoc to fix parameter names and types to match code.

npx tsc --allowJS --checkJS index.js --noEmit
...
Found 35 errors.

[abetomo]

Thanks for the update.