Dependency Extraction Webpack Plugin: prettify dev asset output

[gunjanjaswal]

Fixes #48106.

Right now the generated PHP asset files (*.asset.php and assets.php) get written all on one line, which makes something like script-loader-packages.php annoying to read or diff while you're working on it. This pretty-prints them on the dev (unminified) build so they're readable and diff cleanly. Production builds don't change, they still get the compact one-liner.

The change lives in stringify(): it looks at optimization.minimize, and when that's false it uses json2php.make( { linebreak: '\n', indent: '\t' } ), otherwise it falls back to the compact json2php printer exactly like before. The minify flag comes down from addAssets(), which reads it off compilation.options.optimization.minimize.

To check it, run npm run test:unit packages/dependency-extraction-webpack-plugin, or just build a package in dev mode and open one of the generated *.asset.php files. It's spread over a few indented lines now, and a production build collapses it back to one line.

Use of AI Tools

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