Refactor shared webpack bootstrap into `@wpsyntex/polylang-build-scripts`

[Hug0-Drelon]

What

Every Polylang project repeats the same block at the top of configureWebpack():

const mode = options.mode;
const isProduction = mode === 'production' || false;
const workingDirectory = path.resolve( __dirname );
const jsBuildDirectory = path.join( workingDirectory, 'js/build' );
const cssBuildDirectory = path.join( workingDirectory, 'css/build' );

console.log( 'Webpack mode:', mode );
console.log( 'Working directory:', workingDirectory );

Same code in polylang, polylang-pro, polylang-wc, updater and polylang-for-elementor.

Why

• Duplicated in every repo; any change needs 4+ PRs
• Consumer configs should only define project-specific patterns/entry points
• A shared helper works for both CJS (__dirname) and ESM (import.meta.url)

How

Add a getBuildContext() export:

const { getBuildContext, getVanillaConfig } = require( '@wpsyntex/polylang-build-scripts' );

function configureWebpack( options ) {
	const {
		isProduction,
		workingDirectory,
		jsBuildDirectory,
		cssBuildDirectory,
	} = getBuildContext( options, __dirname, {}, true );

	return getVanillaConfig( {
		workingDirectory,
		jsBuildDirectory,
		cssBuildDirectory,
		isProduction,
		// project-specific options…
	} );
}

Helper sketch:

function getBuildContext(
	options,
	workingDirectory,
	{ jsBuildSubdir = 'js/build', cssBuildSubdir = 'css/build' } = {},
	log = false
) {
	const mode = options?.mode ?? 'development';
	const isProduction = mode === 'production';
	const resolvedWorkingDirectory = path.resolve( workingDirectory );

	if ( log ) {
		console.log( 'Webpack mode:', mode );
		console.log( 'Working directory:', resolvedWorkingDirectory );
	}

	return {
		mode,
		isProduction,
		workingDirectory: resolvedWorkingDirectory,
		jsBuildDirectory: path.join( resolvedWorkingDirectory, jsBuildSubdir ),
		cssBuildDirectory: path.join( resolvedWorkingDirectory, cssBuildSubdir ),
	};
}

Done when: helper exported + documented, unit tests added, all consumer webpack.config.js files