feat: support ESLint 9 and typescript-eslint 7 (#249)

## PR Checklist

- [x] Addresses an existing open issue: fixes #142
- [x] That issue was marked as [`status: accepting
prs`](https://github.com/JoshuaKGoldberg/eslint-plugin-expect-type/issues?q=is%3Aopen+is%3Aissue+label%3A%22status%3A+accepting+prs%22)
- [x] Steps in
[CONTRIBUTING.md](https://github.com/JoshuaKGoldberg/eslint-plugin-expect-type/blob/main/.github/CONTRIBUTING.md)
were taken

## Overview

Adds an `eslint-plugin-expect-type/configs/recommended` export with the
new shape. Touches up the README.md to emphasize flat config over legacy
too.

Also prefers `context.filename` over `context.getFilename()` per
https://eslint.org/blog/2023/05/eslint-v8.40.0-released.

README.md

@@ -48,16 +48,31 @@ npm i -D eslint-plugin-expect-type
 
 ## Usage
 
-Add the following options to your [ESLint configuration file](https://eslint.org/docs/latest/user-guide/configuring/configuration-files):
+Add the following options to your [ESLint configuration file](https://eslint.org/docs/latest/user-guide/configuring/configuration-files-new):
+
+```ts
+import expectType from "eslint-plugin-expect-type/configs/recommended";
+
+export default [
+	// your other ESLint configurations
+	expectType,
+];
+```
+
+Then, you'll be able to use `^?`, `$ExpectError`, `$ExpectType`, and `$ExpectTypeSnapshot` comments in code assert on types.
+
+### Usage (Legacy Config)
+
+If you're still using the [legacy ESLint configuration file format](https://eslint.org/docs/latest/user-guide/configuring/configuration-files):
 
 ```json
 {
 	"extends": ["plugin:expect-type/recommended"],
-	"plugins": ["eslint-plugin-expect-type"]
+	"plugins": ["expect-type"]
 }
 ```
 
-Then, you'll be able to use `^?`, `$ExpectError`, `$ExpectType`, and `$ExpectTypeSnapshot` comments in code assert on types.
+## Rules
 
 <!-- prettier-ignore-start -->
 <!-- begin auto-generated rules list -->

package.json

@@ -40,6 +40,14 @@
 			},
 			"import": "./lib/index.mjs",
 			"require": "./lib/index.js"
+		},
+		"./configs/recommended": {
+			"types": {
+				"import": "./lib/configs/recommended.d.mts",
+				"require": "./lib/configs/recommended.d.ts"
+			},
+			"import": "./lib/configs/recommended.mjs",
+			"require": "./lib/configs/recommended.js"
 		}
 	},
 	"main": "./lib/index.js",
@@ -69,7 +77,7 @@
 		"*": "prettier --ignore-unknown --write"
 	},
 	"dependencies": {
-		"@typescript-eslint/utils": "^6.10.0",
+		"@typescript-eslint/utils": "^6.10.0 || ^7.0.1",
 		"fs-extra": "^11.1.1"
 	},
 	"devDependencies": {
@@ -78,9 +86,10 @@
 		"@types/eslint": "^8.44.7",
 		"@types/fs-extra": "^11.0.0",
 		"@types/node": "^20.0.0",
-		"@typescript-eslint/eslint-plugin": "^7.0.0",
-		"@typescript-eslint/parser": "^7.0.0",
-		"@typescript-eslint/rule-tester": "^7.0.0",
+		"@typescript-eslint/eslint-plugin": "^7.4.0",
+		"@typescript-eslint/parser": "^7.4.0",
+		"@typescript-eslint/rule-tester": "^7.4.0",
+		"@typescript-eslint/utils": "^7.4.0",
 		"@vitest/coverage-v8": "^1.0.0",
 		"console-fail-test": "^0.2.3",
 		"cspell": "^8.0.0",

src/configs/recommended.ts

@@ -0,0 +1,10 @@
+import { plugin, recommendedRuleSettings } from "../plugin.js";
+
+const recommended = {
+	plugins: {
+		"expect-type": plugin,
+	},
+	rules: recommendedRuleSettings,
+};
+
+export default recommended;

src/index.ts

@@ -1,12 +1,10 @@
-import { rules } from "./rules/index.js";
+import { recommendedRuleSettings } from "./plugin.js";
 
 export { rules } from "./rules/index.js";
 
 export const configs = {
 	recommended: {
-		rules: Object.keys(rules).reduce<Record<string, "error">>(
-			(acc, name) => ({ ...acc, [`expect-type/${name}`]: "error" as const }),
-			{},
-		),
+		plugins: ["expect-type"],
+		rules: recommendedRuleSettings,
 	},
 };