fix(path): improper redirects in subpath domain sites

quartz/plugins/pageTypes/dispatcher.ts

@@ -78,10 +78,15 @@ async function emitPage(
 ) {
   const cfg = ctx.cfg.configuration
   // For the 404 page, use an absolute base path so assets resolve correctly
-  // when the hosting provider serves 404.html from any URL depth
+  // when the hosting provider serves 404.html from any URL depth.
+  // During local dev (--serve), the dev server strips baseDir itself and
+  // serves files from root, so the 404 page must use "/" to avoid requesting
+  // assets under a path prefix that the dev server doesn't serve.
   const baseDir =
     slug === "404"
-      ? (new URL(`https://${cfg.baseUrl ?? "example.com"}`).pathname as FullSlug)
+      ? ((ctx.argv.serve
+          ? "/"
+          : new URL(`https://${cfg.baseUrl ?? "example.com"}`).pathname) as FullSlug)
       : pathToRoot(slug)
   const externalResources = pageResources(baseDir, resources)
   const componentData: QuartzComponentProps = {