feat: add opt-in blockESLintPlugin (#2131)

## PR Checklist

- [x] Addresses an existing open issue: fixes #1936
- [x] That issue was marked as [`status: accepting
prs`](https://github.com/JoshuaKGoldberg/create-typescript-app/issues?q=is%3Aopen+is%3Aissue+label%3A%22status%3A+accepting+prs%22)
- [x] Steps in
[CONTRIBUTING.md](https://github.com/JoshuaKGoldberg/create-typescript-app/blob/main/.github/CONTRIBUTING.md)
were taken

## Overview

Adds a Block that devs can use to sync tooling for ESLint plugins built
on CTA. It replaces the default example files with its own, so creating
a new repo will look like:

```shell
npx create-typescript-app --add-eslint-plugin --exclude-example-files
```

🎁

Author: JoshuaKGoldberg

cspell.json

@@ -15,6 +15,7 @@
 		"attw",
 		"boop",
 		"dbaeumer",
+		"eslint-doc-generatorrc.js",
 		"infile",
 		"joshuakgoldberg",
 		"markdownlintignore",

docs/Blocks.md

@@ -23,6 +23,7 @@ This table summarizes each block and which base levels they're included in:
 | ESLint Node Plugin           | `--add-eslint-node-plugin`, `--exclude-eslint-node-plugin`                     |         |        | 💯         |
 | ESLint package.json Plugin   | `--add-eslint-package-json-plugin`, `--exclude-eslint-package-json-plugin`     |         |        | 💯         |
 | ESLint Perfectionist Plugin  | `--add-eslint-perfectionist-plugin`, `--exclude-eslint-perfectionist-plugin`   |         |        | 💯         |
+| ESLint Plugin                | `--add-eslint-plugin`, `--exclude-eslint-plugin`                               |         |        |            |
 | ESLint Regexp Plugin         | `--add-eslint-regexp-plugin`, `--exclude-eslint-regexp-plugin`                 |         |        | 💯         |
 | ESLint YML Plugin            | `--add-eslint-yml-plugin`, `--exclude-eslint-yml-plugin`                       |         |        | 💯         |
 | Funding                      | `--add-funding`, `--exclude-funding`                                           |         | ✅     | 💯         |

src/blocks/blockESLint.test.ts

@@ -465,6 +465,10 @@ describe("blockESLint", () => {
 				imports: [
 					{ source: "eslint-plugin-markdown", specifier: "a", types: true },
 					{ source: "eslint-plugin-regexp", specifier: "b" },
+					{
+						source: { packageName: "eslint-plugin-unknown", version: "1.2.3" },
+						specifier: "c",
+					},
 				],
 				rules: {
 					"a/b": "error",
@@ -536,6 +540,7 @@ describe("blockESLint", () => {
 			            "eslint": "9.22.0",
 			            "eslint-plugin-markdown": "5.1.0",
 			            "eslint-plugin-regexp": "2.7.0",
+			            "eslint-plugin-unknown": "1.2.3",
 			            "typescript-eslint": "8.26.1",
 			          },
 			          "scripts": {
@@ -586,6 +591,7 @@ describe("blockESLint", () => {
 			import eslint from "@eslint/js";
 			import a from "eslint-plugin-markdown"
 			import b from "eslint-plugin-regexp"
+			import c from "eslint-plugin-unknown"
 			import tseslint from "typescript-eslint";
 
 			export default tseslint.config(

src/blocks/blockESLint.ts

@@ -49,7 +49,10 @@ const zExtension = z.object({
 });
 
 const zPackageImport = z.object({
-	source: z.string(),
+	source: z.union([
+		z.string(),
+		z.object({ packageName: z.string(), version: z.string() }),
+	]),
 	specifier: z.string(),
 	types: z.boolean().optional(),
 });
@@ -88,7 +91,7 @@ export const blockESLint = base.createBlock({
 			'import tseslint from "typescript-eslint";',
 			...imports.map(
 				(packageImport) =>
-					`import ${packageImport.specifier} from "${packageImport.source}"`,
+					`import ${packageImport.specifier} from "${typeof packageImport.source === "string" ? packageImport.source : packageImport.source.packageName}"`,
 			),
 		].sort((a, b) =>
 			a.replace(/.+from/, "").localeCompare(b.replace(/.+from/, "")),
@@ -183,17 +186,36 @@ Each should be shown in VS Code, and can be run manually on the command-line:
 				}),
 				blockPackageJson({
 					properties: {
-						devDependencies: getPackageDependencies(
-							"@eslint/js",
-							"@types/node",
-							"eslint",
-							"typescript-eslint",
-							...imports.flatMap(({ source, types }) => {
-								// eslint-disable-next-line @typescript-eslint/no-unsafe-call -- https://github.com/egoist/parse-package-name/issues/30
-								const { name } = parsePackageName(source) as { name: string };
-								return types ? [name, `@types/${name}`] : [name];
-							}),
-						),
+						devDependencies: {
+							...getPackageDependencies(
+								"@eslint/js",
+								"@types/node",
+								"eslint",
+								"typescript-eslint",
+								...imports
+									.filter((imported) => typeof imported.source === "string")
+									.flatMap(({ source, types }) => {
+										// eslint-disable-next-line @typescript-eslint/no-unsafe-call -- https://github.com/egoist/parse-package-name/issues/30
+										const { name } = parsePackageName(source) as {
+											name: string;
+										};
+										return types ? [name, `@types/${name}`] : [name];
+									}),
+							),
+							...Object.fromEntries(
+								imports
+									.filter(
+										(
+											imported,
+										): imported is typeof imported & { source: object } =>
+											typeof imported.source === "object",
+									)
+									.map((imported) => [
+										imported.source.packageName,
+										imported.source.version,
+									]),
+							),
+						},
 						scripts: {
 							lint: "eslint . --max-warnings 0",
 						},