chore(vscode): add markdown-preview-enhanced to extensions list

Author: emylfy

config/vscode/extensions.txt

@@ -12,6 +12,7 @@ ms-azuretools.vscode-containers
 mvllow.rose-pine
 noahraskin.electronic-dawn-theme
 richardluo.frosted-glass-theme
+shd101wyy.markdown-preview-enhanced
 streetsidesoftware.code-spell-checker
 streetsidesoftware.code-spell-checker-cspell-bundled-dictionaries
 subframe7536.custom-ui-style