deps(dev): bump ethers from 6.15.0 to 6.16.0

Bumps [ethers](https://github.com/ethers-io/ethers.js) from 6.15.0 to 6.16.0.
- [Release notes](https://github.com/ethers-io/ethers.js/releases)
- [Changelog](https://github.com/ethers-io/ethers.js/blob/main/CHANGELOG.md)
- [Commits](ethers-io/ethers.js@v6.15.0...v6.16.0)

---
updated-dependencies:
- dependency-name: ethers
  dependency-version: 6.16.0
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

package-lock.json

@@ -26,7 +26,7 @@
     "@types/node": "^24.10.1",
     "eslint-config-prettier": "^10.1.8",
     "eslint-plugin-prettier": "^5.5.4",
-    "ethers": "^6.15.0",
+    "ethers": "^6.16.0",
     "neostandard": "^0.12.2",
     "np": "^10.2.0",
     "prettier": "^3.7.3",