feat: improve skill tests

[cpenned]

---

Summary by cubic

Clarifies the React Email skill to enforce correct Tailwind preset imports and required utility classes for reliable rendering. Adds a new test and broader regression checks to prevent past failures.

• New Features

  • Added “Required Classes” table (Button needs box-border; borders require border-solid; single-side borders reset with border-none).
  • Enforced Tailwind preset import: use pixelBasedPreset from @react-email/components; do not import from @react-email/tailwind or /presets.
  • Added Test A15 for import source and expanded regression checks across scenarios, including pressure tests.

• Migration

  • Import pixelBasedPreset from @react-email/components only.
  • Add box-border to all Buttons.
  • Always set border type; when using one-side borders, reset others with border-none.

^{Written for commit 00e0a3e. Summary will update on new commits.}

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Project	Deployment	Actions	Updated (UTC)
react-email	Ready	Preview, Comment	Feb 12, 2026 7:13pm
react-email-demo	Ready	Preview, Comment	Feb 12, 2026 7:13pm

[changeset-bot]

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Latest commit: 00e0a3e

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[cubic-dev-ai]

No issues found across 2 files

Confidence score: 5/5

• Automated review surfaced no issues in the provided summaries.
• No files require special attention.