docs: add jsdoc to adapters (#7134)

* add contributors and documentation

* docs(adapters): add JSDoc for adapters module

---------

Co-authored-by: Jay <jasonsaayman@gmail.com>

lib/adapters/adapters.js

@@ -4,14 +4,24 @@ import xhrAdapter from './xhr.js';
 import * as fetchAdapter from './fetch.js';
 import AxiosError from "../core/AxiosError.js";
 
+/**
+ * Known adapters mapping.
+ * Provides environment-specific adapters for Axios:
+ * - `http` for Node.js
+ * - `xhr` for browsers
+ * - `fetch` for fetch API-based requests
+ * 
+ * @type {Object<string, Function|Object>}
+ */
 const knownAdapters = {
   http: httpAdapter,
   xhr: xhrAdapter,
   fetch: {
     get: fetchAdapter.getFetch,
   }
-}
+};
 
+// Assign adapter names for easier debugging and identification
 utils.forEach(knownAdapters, (fn, value) => {
   if (fn) {
     try {
@@ -23,12 +33,33 @@ utils.forEach(knownAdapters, (fn, value) => {
   }
 });
 
+/**
+ * Render a rejection reason string for unknown or unsupported adapters
+ * 
+ * @param {string} reason
+ * @returns {string}
+ */
 const renderReason = (reason) => `- ${reason}`;
 
+/**
+ * Check if the adapter is resolved (function, null, or false)
+ * 
+ * @param {Function|null|false} adapter
+ * @returns {boolean}
+ */
 const isResolvedHandle = (adapter) => utils.isFunction(adapter) || adapter === null || adapter === false;
 
-export default {
-  getAdapter: (adapters, config) => {
+/**
+ * Get the first suitable adapter from the provided list.
+ * Tries each adapter in order until a supported one is found.
+ * Throws an AxiosError if no adapter is suitable.
+ * 
+ * @param {Array<string|Function>|string|Function} adapters - Adapter(s) by name or function.
+ * @param {Object} config - Axios request configuration
+ * @throws {AxiosError} If no suitable adapter is available
+ * @returns {Function} The resolved adapter function
+ */
+function getAdapter(adapters, config) {
   adapters = utils.isArray(adapters) ? adapters : [adapters];
 
   const { length } = adapters;
@@ -59,7 +90,6 @@ export default {
   }
 
   if (!adapter) {
-
     const reasons = Object.entries(rejectedReasons)
       .map(([id, state]) => `adapter ${id} ` +
         (state === false ? 'is not supported by the environment' : 'is not available in the build')
@@ -76,6 +106,21 @@ export default {
   }
 
   return adapter;
-  },
-  adapters: knownAdapters
 }
+
+/**
+ * Exports Axios adapters and utility to resolve an adapter
+ */
+export default {
+  /**
+   * Resolve an adapter from a list of adapter names or functions.
+   * @type {Function}
+   */
+  getAdapter,
+
+  /**
+   * Exposes all known adapters
+   * @type {Object<string, Function|Object>}
+   */
+  adapters: knownAdapters
+};