Fix mobile Results layout and review fallbacks

[sgardoll]

Summary

• hide the full-height prompting sidebar when Results is active at mobile widths so the review starts at the top
• ignore empty or malformed bundleReview values when a valid overallReview is available
• add regression coverage for both behaviors

Verification

• npm test (78 passed)
• npm run build
• git diff --check

[greptile-apps]

Greptile Summary

This PR adjusts mobile Results presentation and review payload fallback handling.

• Hides the prompting sidebar while Results is active at mobile widths.
• Selects the first non-empty object among supported overall-review fields.
• Adds regression tests for the responsive CSS and empty/non-object fallback cases.

Confidence Score: 3/5

The PR should not merge until non-empty malformed review objects can no longer shadow a valid fallback review.

The new selection predicate treats every object with a key as valid, so a metadata-only or otherwise malformed bundleReview can still prevent valid overallReview data from reaching the presentation.

Files Needing Attention: src/reviewPresentation.js, src/reviewPresentation.test.js

Important Files Changed

Filename	Overview
index.html	Adds a mobile media rule that hides the sidebar while the full-screen Results state is active.
src/resultsLayout.test.js	Adds a source-level assertion covering the new mobile sidebar CSS rule.
src/reviewPresentation.js	Improves fallback past empty or non-object values, but still lets non-empty malformed objects shadow valid later reviews.
src/reviewPresentation.test.js	Covers empty-object and string fallbacks but omits malformed objects containing irrelevant keys.

Prompt To Fix All With AI

Fix the following 1 code review issue. Work through them one at a time, proposing concise fixes.

---

### Issue 1 of 1
src/reviewPresentation.js:274
**Malformed objects block valid reviews**

When `bundleReview` is a non-empty malformed object such as `{ metadata: {} }`, this predicate selects it solely because it has a key and never reaches a valid `overallReview`, causing the valid score, summary, and findings to be omitted or replaced with fallback presentation values.

_{Reviews (1): Last reviewed commit: "fix: handle mobile results and review fa..." | Re-trigger Greptile}

[greptile-apps]

Malformed objects block valid reviews

When bundleReview is a non-empty malformed object such as { metadata: {} }, this predicate selects it solely because it has a key and never reaches a valid overallReview, causing the valid score, summary, and findings to be omitted or replaced with fallback presentation values.

Prompt To Fix With AI

This is a comment left during a code review.
Path: src/reviewPresentation.js
Line: 274

Comment:
**Malformed objects block valid reviews**

When `bundleReview` is a non-empty malformed object such as `{ metadata: {} }`, this predicate selects it solely because it has a key and never reaches a valid `overallReview`, causing the valid score, summary, and findings to be omitted or replaced with fallback presentation values.

How can I resolve this? If you propose a fix, please make it concise.