[No QA] perf: replace reduce with for-of in reportsByPolicyID to reduce GC pressure

[TMisiukiewicz]

Explanation of Change

Both ReportUtils.ts (the deprecated Onyx connect callback) and outstandingReportsByPolicyID.ts (the OnyxDerived config) built a policy→reports map using Object.entries(...).reduce(...). Each iteration spread the accumulator object ({ ...acc[policyID], [reportID]: report }), creating a new intermediate object per report. On accounts with many reports this produces heavy short-lived allocation, increasing GC pressure.

The change replaces both reduce calls with a plain for...of loop that mutates a local object in place. The result is semantically identical but eliminates the per-iteration spread allocation entirely.

Performance improvement
On Android production build, the total time of both report-grouping loops dropped from ~200ms to ~90ms. The old code rebuilt each policy's bucket with a spread copy on every insert ({...acc[policyID], ...}), generating O(K²) short-lived objects per policy; the new in-place version allocates each bucket once. That churn was also causing GC-pressure spikes up to ~400ms — those are now entirely gone.

Fixed Issues

$ #94985

Tests

No tests needed, pure refactor

• Verify that no errors appear in the JS console

Offline tests

N/A

QA Steps

• Verify that no errors appear in the JS console

PR Author Checklist

• I linked the correct issue in the ### Fixed Issues section above
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Screenshots/Videos

Android: Native

Android: mWeb Chrome

iOS: Native

iOS: mWeb Safari

MacOS: Chrome / Safari

[codecov]

Codecov Report

✅ Changes either increased or maintained existing code coverage, great job!

Files with missing lines	Coverage Δ
src/libs/ReportUtils.ts	85.65% <85.71%> (+0.02%)	⬆️
...nyxDerived/configs/outstandingReportsByPolicyID.ts	94.11% <85.71%> (+0.36%)	⬆️
... and 9 files with indirect coverage changes

[melvin-bot]

@mountiny Please copy/paste the Reviewer Checklist from here into a new comment on this PR and complete it. If you have the K2 extension, you can simply click: [this button]

[ZhenjaHorbach]

Reviewer Checklist

• I have verified the author checklist is complete (all boxes are checked off).
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Screenshots/Videos

Android: HybridApp

2026-06-30.17.10.08.mov

Android: mWeb Chrome

2026-06-30.17.10.08.mov

iOS: HybridApp

2026-06-30.17.18.31.mov

iOS: mWeb Safari

2026-06-30.17.10.08.mov

MacOS: Chrome / Safari

2026-06-30.17.08.19.mov

[OSBotify]

✋ This PR was not deployed to staging yet because QA is ongoing. It will be automatically deployed to staging after the next production release.

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[github-actions]

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[MelvinBot]

🤖 Help site review — no changes required

I reviewed the changes in this PR against the help site articles under App/docs/articles.

This is a pure internal performance refactor: it replaces Object.entries(...).reduce(...) with in-place for...of loops when building the policy→reports maps in src/libs/ReportUtils.ts and src/libs/actions/OnyxDerived/configs/outstandingReportsByPolicyID.ts to reduce GC pressure.

The change is semantically identical to the previous code — no user-facing behavior, feature, UI label, tab name, setting, or copy is added or altered. Help site articles document product behavior for end users, and nothing documented there is affected by this optimization.

Conclusion: No help site changes are required, so no draft docs PR was created.

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🚀 Deployed to production by https://github.com/grgia in version: 9.4.27-2 🚀

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🤖 android 🤖	success ✅
🍎 iOS 🍎	success ✅

Bundle Size Analysis (Sentry):

• Android