fix missing types from exports

Author: JAD3N

package.json

@@ -10,6 +10,7 @@
   "main": "./dist/psl.cjs",
   "exports": {
     ".": {
+      "types": "./types/index.d.ts",
       "import": "./dist/psl.mjs",
       "require": "./dist/psl.cjs"
     }