fix(ci): skip non-e2e build scripts during checks install

[tomcasaburi]

Summary\n- use Yarn skip-build mode in the non-e2e checks job\n- avoid flaky kubo postinstall downloads in the lint/typecheck/unit-test path\n- keep e2e jobs on full installs because they need built runtime dependencies\n\n## Verification\n- yarn lint\n- yarn type-check\n- yarn test:coverage\n- yarn build\n- clean temp checkout: yarn install --immutable --mode=skip-build && same verification suite\n

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Note

Low Risk
Low risk workflow tweak limited to the checks job install step; main risk is missing generated artifacts during lint/typecheck/unit tests if any rely on postinstall/build outputs.

Overview
Updates GitHub Actions CI so the checks job installs dependencies with Yarn --mode=skip-build (instead of running package build/postinstall scripts) before running lint, type-check, and unit tests. The e2e job continues to use a full yarn install --immutable.

^{Written by Cursor Bugbot for commit c7f18d9. This will update automatically on new commits. Configure here.}

Summary by CodeRabbit

• Chores
  • Optimized CI workflow to skip unnecessary build phases during dependency installation, improving build efficiency.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Pro

Run ID: 81d1699b-8f24-4c2a-a8e9-09e552a39889

📥 Commits

Reviewing files that changed from the base of the PR and between ae85d32 and c7f18d9.

📒 Files selected for processing (1)

• .github/workflows/CI.yml

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📝 Walkthrough

Walkthrough

Modified the CI workflow's dependency installation step to add the --mode=skip-build flag to the yarn install command, altering how dependencies are installed during continuous integration checks while preserving immutability constraints.

Changes

Cohort / File(s)	Summary
CI Workflow Configuration .github/workflows/CI.yml	Updated yarn install command in the checks job to include --mode=skip-build flag, skipping build-related phases during dependency installation.

Estimated code review effort

🎯 1 (Trivial) | ⏱️ ~3 minutes

Poem

🐰 A skip-build hop, builds now move fast,
The CI workflow shines at last!
One flag, one change, immutable still—
Swift installations bend to our will. ✨

🚥 Pre-merge checks | ✅ 3

✅ Passed checks (3 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title accurately describes the main change: skipping non-e2e build scripts during the CI checks install step by using yarn's skip-build mode.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.

_{✏️ Tip: You can configure your own custom pre-merge checks in the settings.}

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch fix/ci-kubo-flake

📝 Coding Plan

• Generate coding plan for human review comments

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