@actions/core: convert to ESM module

packages/core/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@actions/core",
-  "version": "2.0.3",
+  "version": "3.0.0",
   "description": "Actions core lib",
   "keywords": [
     "github",
@@ -9,8 +9,15 @@
   ],
   "homepage": "https://github.com/actions/toolkit/tree/main/packages/core",
   "license": "MIT",
+  "type": "module",
   "main": "lib/core.js",
   "types": "lib/core.d.ts",
+  "exports": {
+    ".": {
+      "types": "./lib/core.d.ts",
+      "import": "./lib/core.js"
+    }
+  },
   "directories": {
     "lib": "lib",
     "test": "__tests__"
@@ -36,10 +43,10 @@
     "url": "https://github.com/actions/toolkit/issues"
   },
   "dependencies": {
-    "@actions/exec": "^2.0.0",
-    "@actions/http-client": "^3.0.2"
+    "@actions/exec": "^3.0.0",
+    "@actions/http-client": "^4.0.0"
   },
   "devDependencies": {
-    "@types/node": "^16.18.112"
+    "@types/node": "^25.1.0"
   }
 }