Address new TypeScript warnings in core files, improve type definitions.

lib/md055.mjs

@@ -3,15 +3,16 @@
 import { addErrorDetailIf } from "../helpers/helpers.cjs";
 import { filterByTypesCached } from "./cache.mjs";
 
+/** @typedef {import("markdownlint").MicromarkToken} MicromarkToken */
+/** @typedef {import("micromark-extension-gfm-table")} */
+
 const whitespaceTypes = new Set([ "linePrefix", "whitespace" ]);
-const ignoreWhitespace = (tokens) => tokens.filter(
+const ignoreWhitespace = (/** @type {MicromarkToken[]} */ tokens) => tokens.filter(
   (token) => !whitespaceTypes.has(token.type)
 );
-const firstOrNothing = (items) => items[0];
-const lastOrNothing = (items) => items[items.length - 1];
-const makeRange = (start, end) => [ start, end - start + 1 ];
-
-/** @typedef {import("micromark-extension-gfm-table")} */
+const firstOrNothing = (/** @type {MicromarkToken[]} */ items) => items[0];
+const lastOrNothing = (/** @type {MicromarkToken[]} */ items) => items[items.length - 1];
+const makeRange = (/** @type {number} */ start, /** @type {number} */ end) => [ start, end - start + 1 ];
 
 /** @type {import("markdownlint").Rule} */
 export default {