feat: update AIUI dist (guide as default route) + fix marketplace heading clip

- Rebuild AIUI with guide page as default route (/ -> guide, /chat -> chat)
- Content and context panels start empty
- Fix App Store heading clipped by removing double md:-mt-4 negative margins

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

demo/aiui/assets/clone-DT41vzT6.js

@@ -0,0 +1 @@
+import{b as r}from"./_baseUniq-CenknSnb.js";var e=4;function a(o){return r(o,e)}export{a as c};