Add eslint and stricter TypeScript rules for jspsych package

eslint.config.js

@@ -0,0 +1,34 @@
+import eslint from "@eslint/js";
+import tslint from "typescript-eslint";
+
+export default tslint.config(
+  {
+    ignores: [
+      "docs/*",
+      "examples/*",
+      "packages/*",
+      "!packages/jspsych",
+      "packages/jspsych/*",
+      "!packages/jspsych/src",
+    ],
+  },
+  eslint.configs.recommended,
+  ...tslint.configs.recommended,
+  {
+    rules: {
+      "@typescript-eslint/no-explicit-any": "off",
+      "@typescript-eslint/no-unused-vars": [
+        "error",
+        {
+          args: "all",
+          argsIgnorePattern: "^_",
+          caughtErrors: "all",
+          caughtErrorsIgnorePattern: "^_",
+          destructuredArrayIgnorePattern: "^_",
+          varsIgnorePattern: "^_",
+          ignoreRestSiblings: true,
+        },
+      ],
+    },
+  }
+);