Initial commit: OpenClaw WebUI with LDAP SSO

Features:
- Modern chat interface with streaming responses
- Multi-file upload support
- Code canvas panel for code viewing/editing
- Chat history persistence
- LDAP SSO authentication
- OpenAI-compatible API proxy to OpenClaw gateway
- Model/agent selection
- Dark theme

client/public/favicon.svg

@@ -0,0 +1,4 @@
+<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 100 100">
+  <circle cx="50" cy="50" r="45" fill="none" stroke="#6366f1" stroke-width="6"/>
+  <path d="M28 50 L43 65 L72 30" stroke="#6366f1" stroke-width="8" fill="none" stroke-linecap="round" stroke-linejoin="round"/>
+</svg>