feat(metro-resolver-symlinks): experimental option to retry resolving from disk

[tido64]

Description

Add an experimental option for retrying module resolution from disk if not found in Haste map.

A proper solution would be to implement lazy crawling upstream but that may take some time. In the meantime, this is a workaround that works and doesn't cause too much pollution.

Test plan

This has been tested by a few teams internally.

[tido64]

cc @crazyfraggle @sweggersen @VincentBailly

[afoxman]

So happy to see this idea taking off! I have a few questions/comments. Once we've finalized here, and are using the official @rnx-kit version internally, we should look at publishing the numbers we're seeing, even high-level metrics like "CI builds ran 25% faster (12 mins)".

[tido64]

So happy to see this idea taking off! I have a few questions/comments. Once we've finalized here, and are using the official @rnx-kit version internally, we should look at publishing the numbers we're seeing, even high-level metrics like "CI builds ran 25% faster (12 mins)".

This is definitely something worth writing home about. Vincent's testing saw build time go from 4 min to 27 sec for a single package on a beefy computer.