chore: ban TypeScript enums via lint rule

eslint.config.mjs

@@ -161,6 +161,11 @@ const config = createConfig([
           typescript,
         ]),
         ...NO_CONTROLLER_STATE_CHANGE_SELECTOR_OBJECTS,
+        {
+          selector: 'TSEnumDeclaration',
+          message:
+            "Don't use enums. There are a number of reasons why they are problematic, but the most important is that TypeScript treats them nominally, not structurally, and this can cause unexpected breaking changes. Instead, use an object + type, an array + type, or just a type. Learn more here: https://github.com/MetaMask/eslint-config/issues/417",
+        },
       ],
     },
   },

scripts/create-package/constants.ts

@@ -1,20 +1,24 @@
 /**
  * The monorepo files that need to be parsed or modified.
  */
-export enum MonorepoFiles {
-  PackageJson = 'package.json',
-  TsConfig = 'tsconfig.json',
-  TsConfigBuild = 'tsconfig.build.json',
-}
+export const MonorepoFiles = {
+  PackageJson: 'package.json',
+  TsConfig: 'tsconfig.json',
+  TsConfigBuild: 'tsconfig.build.json',
+} as const;
+
+export type MonorepoFiles = (typeof MonorepoFiles)[keyof typeof MonorepoFiles];
 
 /**
  * Placeholder values in package template files that need to be replaced with
  * actual values corresponding to the new package.
  */
-export enum Placeholders {
-  CurrentYear = 'CURRENT_YEAR',
-  NodeVersions = 'NODE_VERSIONS',
-  PackageName = 'PACKAGE_NAME',
-  PackageDescription = 'PACKAGE_DESCRIPTION',
-  PackageDirectoryName = 'PACKAGE_DIRECTORY_NAME',
-}
+export const Placeholders = {
+  CurrentYear: 'CURRENT_YEAR',
+  NodeVersions: 'NODE_VERSIONS',
+  PackageName: 'PACKAGE_NAME',
+  PackageDescription: 'PACKAGE_DESCRIPTION',
+  PackageDirectoryName: 'PACKAGE_DIRECTORY_NAME',
+} as const;
+
+export type Placeholders = (typeof Placeholders)[keyof typeof Placeholders];