Add structural variants to Testimonial component

[bradpotts]

Added structural variants (elevated, flat, outline, ghost) to the Testimonial component. This brings it in parity with the Card component and provides more flexibility in layout design while maintaining backward compatibility by defaulting to the 'outline' variant.

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PR created automatically by Jules for task 17528705703208929091 started by @bradpotts

Summary by CodeRabbit

Release Notes

• New Features

  • Testimonial component now supports multiple styling variants (elevated, flat, outline, and ghost) with corresponding updated visual theming and styling.

• Tests

  • Updated test coverage to verify variant styling functionality for testimonials.

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No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Pro Plus

Run ID: cbb4c065-ca03-4c21-8bce-f2f65faa247e

📥 Commits

Reviewing files that changed from the base of the PR and between 1f9cbd3 and b073334.

📒 Files selected for processing (4)

• src/recipes/testimonial.ts
• src/styles/components.css
• tests/arsenal-sync.test.ts
• tests/css-contract.test.ts

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📝 Walkthrough

Walkthrough

This PR introduces testimonial variant support to the Spectre UI component library. The change adds four variant options (elevated, flat, outline, ghost) via recipe configuration, CSS token definitions, and corresponding styled selectors. All variant combinations are validated through test coverage updates.

Changes

Testimonial Variant Feature

Layer / File(s)	Summary
Variant recipe contract and resolution src/recipes/testimonial.ts	TESTIMONIAL_VARIANTS map and exported TestimonialVariant type are added, TestimonialRecipeOptions.variant is typed, and getTestimonialClasses resolves the variant option via resolveOption, maps it to the corresponding sp-testimonial--* CSS class, and includes the class in the output.
Testimonial CSS tokens and selectors src/styles/components.css	Component variables layer expanded with testimonial border-base, text, author, quote, shadow, and variant role tokens (elevated/flat/outline/ghost). .sp-testimonial and modifier selectors updated to reference the new tokens, with each variant modifier applying its corresponding shadow and background/border styling.
Variant test coverage tests/arsenal-sync.test.ts, tests/css-contract.test.ts	getTestimonialClasses() test assertion updated to require the outline modifier class. Testimonial selector matrix expanded with axes.variant dimension to validate all four variant combinations.

🎯 2 (Simple) | ⏱️ ~12 minutes

🐰 Four variant friends now dwell,
Elevated, flat, outline, and ghost so well,
CSS tokens map the way,
Tests ensure they work each day,
Testimonials now have more to tell!

🚥 Pre-merge checks | ✅ 3 | ❌ 2

❌ Failed checks (2 warnings)

Check name	Status	Explanation	Resolution
Description check	⚠️ Warning	The description is incomplete. It lacks a linked issue reference, detailed summary of changes, rationale/context, and testing checklist as required by the template.	Add complete information following the template: confirm linked issue, provide detailed summary of file changes, explain the rationale, and include testing checklist items.
Docstring Coverage	⚠️ Warning	Docstring coverage is 0.00% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (3 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title 'Add structural variants to Testimonial component' accurately describes the main change of introducing new layout variants (elevated, flat, outline, ghost) to the component.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

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✨ Finishing Touches

📝 Generate docstrings

• Create stacked PR
• Commit on current branch

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch feat/testimonial-structural-variants-17528705703208929091

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