feat: make css-modules class names human-readable

[Pistch]

Minor improvement to css modules support.
This pull request makes generated css-modules class names human readable (instead of something like kImIF7sZoAjSPn74Hpe8).

Without this improvement css-modules are nearly unusable and are completely undebuggable.

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[ValeraS]

Let's use these options and no other changes will be required.

Suggested change

	...(isCssModuleRules
	? {
	modules: {
	localIdentName: '[name]__[local]--[hash:base64:5]',
	exportLocalsConvention: 'asIs',
	},
	}
	: {}),
	modules: {
	auto: true, // uses modules only with files *.module.s?css
	localIdentName: isEnvDevelopment
	? '[name]__[local]--[hash:base64:5]'
	: '[hash:base64]',
	exportLocalsConvention: 'camelCase', // gives both camel case and as is
	},

[Pistch]

Don't you think readable class names are useful for non-dev environments as well?
I see no harm in exposing those in production builds.
This approach is hardly different from using BEM-naming.

[ValeraS]

We minify all other code except class names, which seems strange to me. And here are source-maps to see original classnames.

[Pistch]

Well, we don't minify BEM classnames. I really doubt we minify css custom property names.

If we were to compare those side-by-side, the difference to total file size seems negligeable:

.MnET1WGLIieyGuzfo5cw {}
.SomeComponent_wrapper-f1da4 {}

Hashes generally have more entropy than variable (or file) names, which leads me to suggest total amount of bytes transferred over network (after gzip/brotli) will be even less for readable names. Didn't measure it, ofc :)

[Pistch]

Here's an example why source maps do not help in this case.
How can i attribute those classes to something in my code?

It is possible to go inside "sources" tab and find something, provided you deployed source maps to static cluster along with bundled code.

[Pistch]

Hey? :]