fix(mobile): prevent Hermes crashes when opening threads

[jakeleventhal]

What Changed

Use sort() and reverse() on freshly allocated arrays in the shared question-answer and tool-activity rendering helpers. Run the mobile thread-feed tests with Array.prototype.toSorted and Array.prototype.toReversed unavailable to match Hermes.

Why

Opening a thread containing an agent question can terminate the mobile release app with TypeError: undefined is not a function. Question folding calls toSorted(), which the bundled Hermes engine does not implement. Tool-activity presentation also calls the unsupported toReversed() method. Desktop supports both methods, so the same threads open successfully there.

The replacements preserve the original input arrays and avoid an unnecessary second copy. The Hermes-compatible test setup reproduces 43 failures before the fix.

Validation

• 174 focused tests pass across mobile thread activity and shared work-log presentation.
• Mobile and client-runtime typechecks pass; changed-file lint, formatting, and git diff --check pass.
• Reproduced the failure with saved activity data from two affected threads and verified both feeds after the fix.
• Rebuilt and installed an iPhone Release app from the personal fork with this patch. Both affected threads open successfully, confirmed by the reporter, with no fatal JavaScript errors in the captured device console.

Checklist

• This PR is small and focused
• I explained what changed and why

Model: GPT-6. Harness: Codex.

Summary by CodeRabbit

• Bug Fixes

  • Improved mobile compatibility by supporting Hermes runtimes that lack newer JavaScript array methods.
  • Ensured work-log processing and question handling continue to function correctly on affected mobile environments.

• Tests

  • Added coverage that simulates the mobile runtime’s available array methods and verifies compatible behavior.

[macroscopeapp]

Approvability

Verdict: Not approved

Macroscope's review found this PR not approvable — This is a narrowly scoped Hermes compatibility fix that preserves existing behavior by sorting and reversing fresh arrays. Human review is still required because the production change adds a line-level lint suppression directive.

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ℹ️ Recent review info

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📥 Commits

Reviewing files that changed from the base of the PR and between 211618f and 6554697.

📒 Files selected for processing (3)

• apps/mobile/src/lib/threadActivity.test.ts
• packages/client-runtime/src/work-log/presentation.ts
• packages/client-runtime/src/work-log/userInput.ts

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📝 Walkthrough

Walkthrough

The change replaces unsupported ES2023 array methods in client-runtime code and updates mobile tests to simulate Hermes by temporarily removing those methods.

Changes

Hermes Array Compatibility

Layer / File(s)	Summary
Replace unsupported array methods packages/client-runtime/src/work-log/presentation.ts, packages/client-runtime/src/work-log/userInput.ts	omitSupersededLifecycleMarkers uses in-place reverse() on a local array. questionFingerprint uses in-place sort() on a local array.
Simulate Hermes array support apps/mobile/src/lib/threadActivity.test.ts	Tests remove toSorted and toReversed before each case and restore their original property descriptors afterward.

Priority: ➖ Normal

Estimated code review effort: 2 (Simple) | ~10 minutes

Change: Bug fix

Suggested reviewers: maria-rcks

Merge Risk: ⚪ Minimal · up to 65546

The Hermes compatibility change removes unsupported array method usage without altering caller-owned arrays, and mobile coverage exercises the affected behavior.

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 0.00% which is insufficient. The required threshold is 80.00%. Docstring coverage is scoped to functions touched by this diff. Analyzed 3 functions across 3 files.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly identifies the mobile Hermes crash fix and matches the primary changes in the pull request.
Description check	✅ Passed	The description includes the required What Changed, Why, and Checklist sections. It also provides detailed validation results. UI-specific sections are not needed because the changes do not modify the…
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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