Custom HTML shell

Pass an HTML file path or template string to htmlShell. Use these placeholders:

Placeholder	Replaced with
`{{mochi.head}}`	`<svelte:head>` content
`{{mochi.css}}`	Scoped component styles
`{{mochi.body}}`	Rendered HTML
	Hydration bootstrap `<script>` tag

await Mochi.serve({
  htmlShell: './src/shell.html',
  routes,
});

Custom placeholders can be injected via transformPageChunk in middleware.