feat: implement build system and development workflow

- Add npm scripts for CSS/JS compilation (build:css, build:js, build)
- Create PowerShell build automation script
- Document development workflow in README
- Add troubleshooting guide for build issues
- Specify proper file structure and compilation process

Supports Tailwind CSS v3.4.0 and esbuild bundling with source maps.

node_modules/tailwindcss/src/postcss-plugins/nesting/README.md

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+# tailwindcss/nesting
+
+This is a PostCSS plugin that wraps [postcss-nested](https://github.com/postcss/postcss-nested) or [postcss-nesting](https://github.com/csstools/postcss-plugins/tree/main/plugins/postcss-nesting) and acts as a compatibility layer to make sure your nesting plugin of choice properly understands Tailwind's custom syntax like `@apply` and `@screen`.
+
+Add it to your PostCSS configuration, somewhere before Tailwind itself:
+
+```js
+// postcss.config.js
+module.exports = {
+  plugins: [
+    require('postcss-import'),
+    require('tailwindcss/nesting'),
+    require('tailwindcss'),
+    require('autoprefixer'),
+  ]
+}
+```
+
+By default, it uses the [postcss-nested](https://github.com/postcss/postcss-nested) plugin under the hood, which uses a Sass-like syntax and is the plugin that powers nesting support in the [Tailwind CSS plugin API](https://tailwindcss.com/docs/plugins#css-in-js-syntax).
+
+If you'd rather use [postcss-nesting](https://github.com/csstools/postcss-plugins/tree/main/plugins/postcss-nesting) (which is based on the work-in-progress [CSS Nesting](https://drafts.csswg.org/css-nesting-1/) specification), first install the plugin alongside:
+
+```shell
+npm install postcss-nesting
+```
+
+Then pass the plugin itself as an argument to `tailwindcss/nesting` in your PostCSS configuration:
+
+```js
+// postcss.config.js
+module.exports = {
+  plugins: [
+    require('postcss-import'),
+    require('tailwindcss/nesting')(require('postcss-nesting')),
+    require('tailwindcss'),
+    require('autoprefixer'),
+  ]
+}
+```
+
+This can also be helpful if for whatever reason you need to use a very specific version of `postcss-nested` and want to override the version we bundle with `tailwindcss/nesting` itself.
+

node_modules/tailwindcss/src/postcss-plugins/nesting/index.js

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+import { nesting } from './plugin'
+
+export default Object.assign(
+  function (opts) {
+    return {
+      postcssPlugin: 'tailwindcss/nesting',
+      Once(root, { result }) {
+        return nesting(opts)(root, result)
+      },
+    }
+  },
+  { postcss: true }
+)

node_modules/tailwindcss/src/postcss-plugins/nesting/plugin.js

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+import postcss from 'postcss'
+import postcssNested from 'postcss-nested'
+
+export function nesting(opts = postcssNested) {
+  return (root, result) => {
+    root.walkAtRules('screen', (rule) => {
+      rule.name = 'media'
+      rule.params = `screen(${rule.params})`
+    })
+
+    root.walkAtRules('apply', (rule) => {
+      rule.before(postcss.decl({ prop: '__apply', value: rule.params, source: rule.source }))
+      rule.remove()
+    })
+
+    let plugin = (() => {
+      if (
+        typeof opts === 'function' ||
+        (typeof opts === 'object' && opts?.hasOwnProperty?.('postcssPlugin'))
+      ) {
+        return opts
+      }
+
+      if (typeof opts === 'string') {
+        return require(opts)
+      }
+
+      if (Object.keys(opts).length <= 0) {
+        return postcssNested
+      }
+
+      throw new Error('tailwindcss/nesting should be loaded with a nesting plugin.')
+    })()
+
+    postcss([plugin]).process(root, result.opts).sync()
+
+    root.walkDecls('__apply', (decl) => {
+      decl.before(postcss.atRule({ name: 'apply', params: decl.value, source: decl.source }))
+      decl.remove()
+    })
+
+    /**
+     * Use a private PostCSS API to remove the "clean" flag from the entire AST.
+     * This is done because running process() on the AST will set the "clean"
+     * flag on all nodes, which we don't want.
+     *
+     * This causes downstream plugins using the visitor API to be skipped.
+     *
+     * This is guarded because the PostCSS API is not public
+     * and may change in future versions of PostCSS.
+     *
+     * See https://github.com/postcss/postcss/issues/1712 for more details
+     *
+     * @param {import('postcss').Node} node
+     */
+    function markDirty(node) {
+      if (!('markDirty' in node)) {
+        return
+      }
+
+      // Traverse the tree down to the leaf nodes
+      if (node.nodes) {
+        node.nodes.forEach((n) => markDirty(n))
+      }
+
+      // If it's a leaf node mark it as dirty
+      // We do this here because marking a node as dirty
+      // will walk up the tree and mark all parents as dirty
+      // resulting in a lot of unnecessary work if we did this
+      // for every single node
+      if (!node.nodes) {
+        node.markDirty()
+      }
+    }
+
+    markDirty(root)
+
+    return root
+  }
+}