metro: add support for unstable_enablePackageExports

[tido64]

Metro 0.75.1 will be the first version with support for exports map: facebook/metro#670 (comment)

We need to make sure that when this flag is enabled, our plugins will also honor it.

[The-White-Fang]

I am not sure if I was using it correctly but for me, this option was not working when used with @rnx-kit/metro-resolver-symlinks

I was using the following config

const { makeMetroConfig } = require('@rnx-kit/metro-config');
const MetroSymlinksResolver = require('@rnx-kit/metro-resolver-symlinks');

module.exports = makeMetroConfig({
	projectRoot: __dirname,
	resolver: {
		resolveRequest: MetroSymlinksResolver(),
		unstable_enablePackageExports: true,
	},
});

After removing @rnx-kit/metro-resolver-symlinks and replacing it with unstable_enableSymlinks everything started working fine again.

This is the updated config

const { makeMetroConfig } = require('@rnx-kit/metro-config');

module.exports = makeMetroConfig({
	projectRoot: __dirname,
	resolver: {
		unstable_enableSymlinks: true,
		unstable_enablePackageExports: true,
	},
});

[tido64]

I am not sure if I was using it correctly but for me, this option was not working when used with @rnx-kit/metro-resolver-symlinks

Hi, can you open a bug report here: https://github.com/microsoft/rnx-kit/issues/new?assignees=&labels=bug&projects=&template=bug_report.yml

We need more details to help you investigate this. When you say "working fine again", what exactly didn't work before? Did it crash? Did the bundling fail? Did the app fail to run? And most importantly, we want a minimal repro. If we cannot reproduce the error you're seeing, we cannot help you.