Added support for customizing processors in `scripts.js` (esbuild), `styles.js` (node-sass, postcss, autoprefixer), and `svgs.js` (svg-mixer), via arguments for the exported task functions.
Added:
- Constants to decouple shared default options, options for development, and options for production.
- Constants to export default options for development and production as an array of arguments to pass to task functions.
Changed:
- watch.js to apply development args to tasks
Added:
- Utility 'postcss.js' to use dynamic imports to fetch PostCSS and Autoprefixer, if available, and build the Processor object.
- Function `saveStylesheet()` in 'styles.js' to decouple the writing of CSS files and source maps.
- Condition to process with PostCSS if it's available.
