Migrate to eslint 9 config file format

eslint.config.js

@@ -0,0 +1,26 @@
+import js from "@eslint/js";
+import react from "@eslint-react/eslint-plugin";
+import * as tsParser from "@typescript-eslint/parser";
+
+export default [
+    js.configs.recommended,
+    {
+      files: ["**/*.{js,jsx}"],
+      ...react.configs.recommended,
+      languageOptions: {
+        parser: tsParser,
+      },
+      rules: {
+        "no-console": "error",
+        "no-undef": "warn"
+      }
+    },
+    {
+      files: ["example/**/*.{js,jsx}"],
+      settings: {
+        "react-x": {
+          importSource: "theme-ui"
+        }
+      },
+    }
+];

package.json

@@ -34,7 +34,7 @@
     "watch": "vite build -w",
     "test": "vitest run",
     "test:watch": "vitest watch",
-    "lint": "eslint --ext .js,.jsx src example/src",
+    "lint": "eslint src example/src",
     "deploy": "yarn install && yarn run build && cd example && yarn install && yarn run build",
     "compile": "tsc"
   },
@@ -43,6 +43,8 @@
     "react-dom": "^18.2.0"
   },
   "devDependencies": {
+    "@eslint-react/eslint-plugin": "^1.14.2",
+    "@eslint/js": "^9.11.1",
     "@rollup/plugin-eslint": "^9.0.5",
     "@testing-library/dom": "^10.4.0",
     "@testing-library/jest-dom": "^6.5.0",
@@ -53,10 +55,9 @@
     "@typescript-eslint/parser": "^8.7.0",
     "csstype": "^3.1.3",
     "eslint": "^9.11.1",
-    "eslint-config-react-app": "^7.0.1",
     "jsdom": "^25.0.1",
-    "react": "^18.3.1",
-    "react-dom": "^18.3.1",
+    "react": "^18.2.0",
+    "react-dom": "^18.2.0",
     "react-test-renderer": "^18.3.1",
     "typescript": "^5.6.2",
     "vite": "^5.4.8",