feat: Bundler with tsdown

package.json

@@ -5,14 +5,14 @@
   "description": "WordPress operations CLI for Websimple projects.",
   "author": "Pascal Martineau <pascal@lewebsimple.ca>",
   "bin": {
-    "wpop": "./dist/cli.js"
+    "wpop": "./dist/cli.mjs"
   },
   "files": [
     "dist"
   ],
   "type": "module",
   "scripts": {
-    "build": "tsc -p tsconfig.json",
+    "build": "tsdown",
     "changelog": "changelogen",
     "check": "npm run format:check && npm run lint && npm run typecheck",
     "dev": "tsx src/cli.ts",
@@ -39,6 +39,7 @@
     "lint-staged": "^17.0.2",
     "oxfmt": "^0.48.0",
     "oxlint": "^1.63.0",
+    "tsdown": "^0.22.0",
     "tsx": "^4.21.0",
     "typescript": "^6.0.3"
   },