Fix missing prose styles in production by converting Tailwind config to JS

The production Docker build (node:22-alpine) was failing to load the
TypeScript Tailwind config via jiti, causing Tailwind to silently fall
back to a default config with no plugins. This meant the
@tailwindcss/typography plugin never ran, so no .prose CSS rules were
generated. Tailwind's preflight reset (p { margin: 0 }) was still
applied with nothing to override it, making all blog post paragraphs
run together with zero spacing.

Converting tailwind.config.ts and typography.ts to plain JS files
removes the dependency on jiti for config loading. Also adds .mdx to
the Tailwind content glob so utility classes used directly in MDX files
(not-prose, flex, etc.) are included in the production CSS.

src/app/news/2026-04-02-endurance/page.mdx

@@ -1,6 +1,6 @@
 import { ArticleLayout } from '@/components/ArticleLayout'
 import {MdxImage as Image } from '@/components/MdxImage'
-import endurance from './endurance.webp'
+import endurance from './endurance.png'
 
 export const article = {
   author: 'Leslie Brown',

tailwind.config.js

@@ -1,11 +1,11 @@
-import typographyPlugin from '@tailwindcss/typography'
-import formsPlugin from '@tailwindcss/forms';
-import { type Config } from 'tailwindcss'
+const typographyPlugin = require('@tailwindcss/typography')
+const formsPlugin = require('@tailwindcss/forms')
 
-import typographyStyles from './typography'
+const typographyStyles = require('./typography')
 
-export default {
-  content: ['./src/**/*.{js,jsx,ts,tsx}'],
+/** @type {import('tailwindcss').Config} */
+module.exports = {
+  content: ['./src/**/*.{js,jsx,mdx,ts,tsx}'],
   darkMode: 'class',
   plugins: [
     typographyPlugin,
@@ -29,4 +29,4 @@ export default {
     },
     typography: typographyStyles,
   },
-} satisfies Config
+}

typography.js

@@ -1,6 +1,4 @@
-import { type PluginUtils } from 'tailwindcss/types/config'
-
-export default function typographyStyles({ theme }: PluginUtils) {
+module.exports = function typographyStyles({ theme }) {
   return {
     invert: {
       css: {