perf: improve native apps startup

[hurali97]

Details

The changes in the PR are part of improving the app startup which was profiled for the native Apps. The main change is explained below, the other changes are self explanatory.

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Prior to the following change, we had 2.4 seconds being consumed in the loop. We can improve this by doing a multiGet and then doing a loop over returned keys. This reduces the execution time to 250 ms, saving us 2 seconds.

Before:

After:

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Related Issues

https://github.com/Expensify/App/issues/43746

Automated Tests

Manual Tests

Author Checklist

• [X] I linked the correct issue in the ### Related Issues section above
• [X] I wrote clear testing steps that cover the changes made in this PR
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• [X] I included screenshots or videos for tests on all platforms
• [X] I ran the tests on all platforms & verified they passed on:
  • [X] Android / native
  • [X] Android / Chrome
  • [X] iOS / native
  • [X] iOS / Safari
  • [X] MacOS / Chrome / Safari
  • [X] MacOS / Desktop
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Screenshots/Videos

Android: Native

https://github.com/Expensify/react-native-onyx/assets/47336142/a0e2ff33-eb62-45ad-8aed-fb2bddcb18ea

Android: mWeb Chrome

https://github.com/Expensify/react-native-onyx/assets/47336142/16ab1920-f82f-4b1e-8160-7594bddaa272

iOS: Native

https://github.com/Expensify/react-native-onyx/assets/47336142/a215f721-a281-4937-8ba9-931404a353bd

iOS: mWeb Safari

https://github.com/Expensify/react-native-onyx/assets/47336142/7f24c6fa-ac8c-482e-842a-1c5f7d778ff9

MacOS: Chrome / Safari

https://github.com/Expensify/react-native-onyx/assets/47336142/728ef8b3-86c1-404f-8945-276258902834

MacOS: Desktop

https://github.com/Expensify/react-native-onyx/assets/47336142/983b0783-5836-460b-8c26-e5716542f9b9

[hurali97]

Looks great overall. I think we can re-use some existing code.

I'm also curious if the for in loops are really helping performance / memory use or if that was just a preference. Disabling eslint is probably fine because I don't think we'll have prototype properties getting in the way, but let's only disable the rule if there's a good reason.

Comparing the before and after profiles, we get 400ms of reduction if we use for...in mainly because we are not doing Object.keys first for target and second for source. These numbers are really noticeable on a large data like ~15k reports.

[hurali97]

@chrispader @hannojg suggested changes are addressed, would be great to if you guys can re-review 👍

[neil-marcellini]

@hannojg do you want to review once more before we merge? @mountiny feel free to go ahead if you want.

[github-actions[bot]]

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