Add d.cts export

Author: cyanzhong

README.md

@@ -19,7 +19,7 @@ Add `markedit-api` to your (TypeScript) project's devDependencies:
 ```json
 {
   "devDependencies": {
-    "markedit-api": "https://github.com/MarkEdit-app/MarkEdit-api#v0.26.0"
+    "markedit-api": "https://github.com/MarkEdit-app/MarkEdit-api#v0.27.0"
   }
 }
 ```

index.d.cts

@@ -0,0 +1 @@
+export * from './index.js';

package.json

@@ -1,10 +1,23 @@
 {
   "name": "markedit-api",
-  "version": "0.26.0",
+  "version": "0.27.0",
   "description": "Type definitions for the latest MarkEdit API.",
+  "type": "module",
   "main": "./index.cjs",
   "module": "./index.js",
   "types": "./index.d.ts",
+  "exports": {
+    ".": {
+      "import": {
+        "types": "./index.d.ts",
+        "default": "./index.js"
+      },
+      "require": {
+        "types": "./index.d.cts",
+        "default": "./index.cjs"
+      }
+    }
+  },
   "license": "MIT",
   "peerDependencies": {
     "@codemirror/autocomplete": "^6.0.0",