chore(deps-dev): bump @earendil-works/pi-coding-agent

Bumps [@earendil-works/pi-coding-agent](https://github.com/earendil-works/pi/tree/HEAD/packages/coding-agent) from 0.85.1 to 0.87.1.
- [Release notes](https://github.com/earendil-works/pi/releases)
- [Changelog](https://github.com/earendil-works/pi/blob/main/packages/coding-agent/CHANGELOG.md)
- [Commits](https://github.com/earendil-works/pi/commits/v0.87.1/packages/coding-agent)

---
updated-dependencies:
- dependency-name: "@earendil-works/pi-coding-agent"
  dependency-version: 0.87.1
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

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Author: dependabot[bot]