fix: use self-portaling DetailPanel from design system v0.1.5

DetailPanel now portals itself to #cameleer-detail-panel-root (a div
AppShell places as a sibling of .main in the top-level flex row).
Pages just render <DetailPanel> inline — no manual createPortal,
no context, no prop drilling.

Remove the old #detail-panel-portal div from LayoutShell and the
createPortal wrappers from Dashboard and AgentHealth.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

ui/package.json

@@ -14,7 +14,7 @@
     "generate-api:live": "curl -s http://localhost:8081/api/v1/api-docs -o src/api/openapi.json && openapi-typescript src/api/openapi.json -o src/api/schema.d.ts"
   },
   "dependencies": {
-    "@cameleer/design-system": "^0.1.4",
+    "@cameleer/design-system": "^0.1.5",
     "@tanstack/react-query": "^5.90.21",
     "openapi-fetch": "^0.17.0",
     "react": "^19.2.4",