chore(deps-dev): Bump tsdown from 0.19.0 to 0.20.1

Bumps [tsdown](https://github.com/rolldown/tsdown) from 0.19.0 to 0.20.1.
- [Release notes](https://github.com/rolldown/tsdown/releases)
- [Commits](rolldown/tsdown@v0.19.0...v0.20.1)

---
updated-dependencies:
- dependency-name: tsdown
  dependency-version: 0.20.1
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

package.json

@@ -19,7 +19,7 @@
     "make-fetch-happen": "^15.0.3",
     "npm-run-all": "^4.1.5",
     "prettier": "^3.7.4",
-    "tsdown": "^0.19.0",
+    "tsdown": "^0.20.1",
     "typescript": "^5.3.3",
     "typescript-eslint": "^8.49.0",
     "vitest": "^4.0.15"