build(deps-dev): bump prettier-eslint-cli to 9 (with prettier-eslint 17)

[matthewhanson]

Summary

Replaces dependabot #1126, which failed at npm install with ERESOLVE.

prettier-eslint-cli@9.2.1 requires prettier-eslint >=17.0.1, but the bump landed alone against prettier-eslint@16.4.2. This bumps the pair together (prettier-eslint → ^17.1.1, prettier-eslint-cli → ^9.2.1); prettier stays ^3.8.4.

Verification

npm install resolves cleanly, typecheck ✓, lint ✓ (full CI on this PR).

Closes #1126

🤖 Generated with Claude Code

[Copilot]

Pull request overview

This PR updates the dev formatting toolchain by bumping prettier-eslint-cli to v9 and prettier-eslint to v17 to resolve an npm peer dependency conflict (per the linked dependabot failure).

Changes:

• Bump prettier-eslint from ^16.4.2 → ^17.1.1
• Bump prettier-eslint-cli from ^8.0.1 → ^9.2.1
• Refresh package-lock.json to reflect the new dependency graph

Reviewed changes

Copilot reviewed 1 out of 2 changed files in this pull request and generated 1 comment.

File	Description
package.json	Updates devDependencies to the compatible prettier-eslint / prettier-eslint-cli pair.
package-lock.json	Captures the resolved dependency tree for the bumped formatter tooling (incl. new transitive deps).

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[matthewhanson]

Re: Copilot's note about transitive Node-engine requirements vs the docs workflow pinning Node 20 — good catch. Rather than touch the workflow here, I've aligned docs.yml to .nvmrc (Node 22) and declared engines.node >=22 in #1134 (got 15 has the hard Node 22 requirement), which covers this PR's looser >=20.19 transitive reqs too. Suggest merging #1134 alongside/before this so all CI is on Node 22. No change needed here.