fix(objectos): add tsup as devDependency for build tooling

Co-authored-by: hotlong <50353452+hotlong@users.noreply.github.com>

Author: Claude

packages/objectos/package.json

@@ -39,6 +39,7 @@
   "devDependencies": {
     "@types/node": "^25.6.0",
     "@vitest/coverage-v8": "^4.1.4",
+    "tsup": "^8.5.1",
     "tsx": "^4.21.0",
     "typescript": "^6.0.2",
     "vitest": "^4.1.4"