refactor(eslint-plugin-react-hooks): move rules to rules folder

Since the compiler plugin is going to be merged into the hooks plugin,, and ultimately decomposed into several more rules, it would be good to start creating a more traditional folder structure for the plugin.  This change just moves the rules into a `rules` folder.

Author: michaelfaith

packages/eslint-plugin-react-hooks/README.md

@@ -36,7 +36,7 @@ If you are still using ESLint below 9.0.0, please continue to use `recommended-l
 For [ESLint 9.0.0 and above](https://eslint.org/blog/2024/04/eslint-v9.0.0-released/) users, add the `recommended-latest` config.
 
 ```js
-import reactHooks from 'eslint-plugin-react-hooks';
+import * as reactHooks from 'eslint-plugin-react-hooks';
 
 export default [
   // ...
@@ -67,7 +67,7 @@ If you want more fine-grained configuration, you can instead add a snippet like
 #### Flat Config (eslint.config.js)
 
 ```js
-import reactHooks from 'eslint-plugin-react-hooks';
+import * as reactHooks from 'eslint-plugin-react-hooks';
 
 export default [
   {

packages/eslint-plugin-react-hooks/src/index.ts

@@ -4,8 +4,8 @@
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
  */
-import RulesOfHooks from './RulesOfHooks';
-import ExhaustiveDeps from './ExhaustiveDeps';
+import RulesOfHooks from './rules/RulesOfHooks';
+import ExhaustiveDeps from './rules/ExhaustiveDeps';
 import type {ESLint, Linter, Rule} from 'eslint';
 
 // All rules