refactor(store): split gatewayStore into specialized domain stores

Major restructuring:
- Split monolithic gatewayStore into 5 focused stores:
  - connectionStore: WebSocket connection and gateway lifecycle
  - configStore: quickConfig, workspaceInfo, MCP services
  - agentStore: clones, usage stats, agent management
  - handStore: hands, approvals, triggers, hand runs
  - workflowStore: workflows, workflow runs, execution

- Update all components to use new stores with selector pattern
- Remove

desktop/src/components/CloneManager.tsx

@@ -1,12 +1,18 @@
 import { useState, useEffect } from 'react';
-import { useGatewayStore } from '../store/gatewayStore';
+import { useAgentStore } from '../store/agentStore';
+import { useConnectionStore } from '../store/connectionStore';
+import { useConfigStore } from '../store/configStore';
 import { toChatAgent, useChatStore } from '../store/chatStore';
 import { Bot, Plus, X, Globe, Cat, Search, BarChart2, Sparkles } from 'lucide-react';
 import { AgentOnboardingWizard } from './AgentOnboardingWizard';
 import type { Clone } from '../store/agentStore';
 
 export function CloneManager() {
-  const { clones, loadClones, deleteClone, connectionState, quickConfig } = useGatewayStore();
+  const clones = useAgentStore((s) => s.clones);
+  const loadClones = useAgentStore((s) => s.loadClones);
+  const deleteClone = useAgentStore((s) => s.deleteClone);
+  const connectionState = useConnectionStore((s) => s.connectionState);
+  const quickConfig = useConfigStore((s) => s.quickConfig);
   const { agents, currentAgent, setCurrentAgent } = useChatStore();
   const [showWizard, setShowWizard] = useState(false);