feat(task) : add markdown preview for task description

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

frontend/tailwind.config.ts

@@ -1,7 +1,9 @@
 import type {Config} from 'tailwindcss'
+import typography from '@tailwindcss/typography'
 
 export default <Partial<Config>>{
     darkMode: 'class',
+    plugins: [typography],
     theme: {
         extend: {
             fontFamily: {