chore: dedupe yarn.lock in renovate PRs

[rekmarks-consensys-1]

Renovate PRs leave duplicate entries in yarn.lock, so lint:dependencies (yarn dedupe --check) fails until someone checks out the branch and runs yarn dedupe by hand. This makes Renovate run the dedupe itself.

• Adds "postUpdateOptions": ["yarnDedupeHighest"] to renovate.json. Per the Renovate docs, this runs yarn dedupe --strategy highest after yarn.lock updates on Yarn >=2.2.0. Renovate passes the same flags as its yarn install step, i.e. --mode=update-lockfile, which the allow-scripts hook already skips since fix: skip allow-scripts hook under update-lockfile mode #1140.

Testing

Renovate config can't be exercised locally; the next Renovate npm PR should arrive with a deduped lockfile.

🤖 Generated with Claude Code

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Note

Low Risk
Renovate-only configuration change; no application or CI script logic is modified beyond automated lockfile maintenance.

Overview
Configures Renovate to run yarn dedupe --strategy highest after it updates yarn.lock, via postUpdateOptions: yarnDedupeHighest in renovate.json.

That should stop Renovate dependency PRs from leaving duplicate lockfile entries that fail root lint:dependencies (yarn dedupe --check) until someone manually dedupes the branch.

^{Reviewed by Cursor Bugbot for commit 687b04f. Bugbot is set up for automated code reviews on this repo. Configure here.}

[github-actions]

Coverage Report

Status	Category	Percentage	Covered / Total
🔵	Lines	73.15% 🟰 ±0%	9880 / 13505
🔵	Statements	72.95% ⬆️ +0.01%	10011 / 13723
🔵	Functions	73.55% 🟰 ±0%	2311 / 3142
🔵	Branches	67.53% ⬆️ +0.01%	4080 / 6041

File Coverage

No changed files found.

Generated in workflow #5121 for commit 687b04f by the Vitest Coverage Report Action

[ci-belphegor]

The esteemed thinking machine duped itself, after each unraveling a fragment further from the world