chore(deps): update dependency tsdown to v0.16.8

Author: renovate[bot]

package.json

@@ -38,7 +38,7 @@
     "knip": "5.70.2",
     "lint-staged": "16.2.7",
     "prettier": "3.7.1",
-    "tsdown": "0.16.7",
+    "tsdown": "0.16.8",
     "typescript": "5.9.3",
     "vitest": "4.0.14"
   },