fix(ios): keep the fresh-install directory layout on clear-app-state

[pvedula7]

Summary

Follow-up to #3156. On an iOS simulator, settings clear-app-state removes the data container's top-level directories, not just their contents. On relaunch iOS recreates Documents and Library, but not tmp or SystemData. Without tmp, every URLSession download task fails until the app is reinstalled. We hit it as Expo's asset loader failing to fetch fonts (UnableToDownloadAssetException) after app.clearState(), while plain data requests kept working.

After clearing, the container now gets back the directories a fresh install has (Documents, Library/Caches, Library/Preferences, SystemData, tmp), empty. 3 files: the fix, its unit test, and the commands doc.

Validation

• 528b66ee9: pnpm check:affected --run passes. The extended app-settings.test.ts case fails on main.
• iOS 26.5 simulator, Xcode 26.6, Expo SDK 57 dev-client app. Data container after settings clear-app-state <bundle> and a relaunch:
  • fresh install: Documents, Library/{Caches,Preferences}, SystemData, tmp
  • main: no tmp or SystemData; asset downloads fail
  • this branch: same layout as a fresh install; assets load
• Risk: the directory list is what iOS 26.5 creates; other runtimes could differ.

[cubic-dev-ai]

All reported issues were addressed across 3 files

<sub>Reply with feedback, questions, or to request a fix.

Re-trigger cubic</sub>

[thymikee]

The PR is ready at 528b66e. The code keeps the fresh-install directory layout on clear-app-state as intended, and I found no problems in the change.

Not blocking: the directory list in app-settings.ts matches the iOS 26.5 layout, so a short note in the commands.md sentence or the constant's comment would say so, since older runtimes and tvOS or visionOS simulators could differ. Extra empty directories are harmless because the old code already wiped those containers. You can take this or leave it.

The Cubic P2 thread on the tvOS and visionOS guard still applies, but it is the same documentation caveat and not a defect (#3198 (comment)). The Cubic P3 thread on non-atomic mkdir does not apply, so please resolve it: a mkdir failure surfaces as an error, and a rerun converges to the full layout (#3198 (comment)).

The one reported check passed, and it covers the route this diff touches (clearIosSimulatorAppState and its unit test). I did not run the unit test or any simulator. The regression claim comes from reading the diff. The iOS 26.5 live validation and the claim that asset downloads fail on main come from the PR body. I did not check the layout on other iOS runtimes, tvOS or visionOS. No conflicts are known, and nothing else must happen before merge.

[pvedula7]

Added the note in 3791616: the comment on FRESH_INSTALL_DATA_DIRECTORIES and the clear-app-state line in commands.md now say the list matches the iOS 26.5 fresh-install layout and other runtimes may differ. No code changes.

[thymikee]

I re-reviewed this PR at 3791616 and found no code problems. Since the earlier review at 528b66e, the new commit changes comments and docs only, so the code I reviewed before still stands. The one check reported on this head passes, and there are no conflicts. I did not check the iOS 26.5 layout claim on a live simulator, and I did not individually verify the two resolved threads. The delta does not touch their code. Nothing else must happen before merge.