fix(studio): serve favicon.svg from embedded preview server (#806)

The /favicon.svg request was falling through to the SPA catch-all, which
returns index.html. The browser received HTML instead of an SVG and
silently discarded it, leaving the tab with no icon.

Added an explicit route for /favicon.svg alongside the existing /assets/*
and /icons/* static routes.

Closes #804

Author: miguel-heygen

packages/cli/src/server/studioServer.ts

@@ -420,6 +420,7 @@ export function createStudioServer(options: StudioServerOptions): StudioServer {
   };
   app.get("/assets/*", serveStudioStaticFile);
   app.get("/icons/*", serveStudioStaticFile);
+  app.get("/favicon.svg", serveStudioStaticFile);
 
   // SPA fallback
   app.get("*", (c) => {