chore: update to eslint v9 (#24)

.gitignore

@@ -2,6 +2,7 @@
 !jest.config.js
 *.d.ts
 node_modules
+!eslint.config.js
 
 # CDK asset staging directory
 .cdk.staging

eslint.config.js

@@ -0,0 +1,24 @@
+const pluginJs = require("@eslint/js");
+const tseslint = require("typescript-eslint");
+const prettier = require("eslint-config-prettier");
+
+module.exports = [
+  { files: ["**/*.ts"] },
+  {
+    languageOptions: {
+      parserOptions: {
+        project: "./tsconfig.json",
+      },
+    },
+  },
+  pluginJs.configs.recommended,
+  ...tseslint.configs.recommended,
+  {
+    rules: {
+      ...prettier.rules,
+    },
+  },
+  {
+    ignores: ["**/*.d.ts"],
+  },
+];