fix(cli): wire initialModel/initialProvider through useSocket, add error handling

- Pass initialModel/initialProvider from CLI flags into useSocket hook
- Include provider/modelId in socket message emit (restores PR #144 functionality)
- Add provider/modelId optional fields to ChatMessagePayload type
- Add .catch() to floating promises in createConversation/deleteConversation

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

packages/cli/src/tui/hooks/use-socket.ts

@@ -41,6 +41,8 @@ export interface UseSocketOptions {
   gatewayUrl: string;
   sessionCookie?: string;
   initialConversationId?: string;
+  initialModel?: string;
+  initialProvider?: string;
 }
 
 export interface UseSocketReturn {
@@ -78,7 +80,7 @@ const EMPTY_USAGE: TokenUsage = {
 };
 
 export function useSocket(opts: UseSocketOptions): UseSocketReturn {
-  const { gatewayUrl, sessionCookie, initialConversationId } = opts;
+  const { gatewayUrl, sessionCookie, initialConversationId, initialModel, initialProvider } = opts;
 
   const [connected, setConnected] = useState(false);
   const [connecting, setConnecting] = useState(true);
@@ -227,6 +229,8 @@ export function useSocket(opts: UseSocketOptions): UseSocketReturn {
       socketRef.current.emit('message', {
         conversationId,
         content,
+        ...(initialProvider ? { provider: initialProvider } : {}),
+        ...(initialModel ? { modelId: initialModel } : {}),
       });
     },
     [conversationId, isStreaming],