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/store/teamStore.ts

@@ -24,8 +24,6 @@ import type {
   ReviewFeedback,
   TaskDeliverable,
 } from '../types/team';
-import { parseJsonOrDefault } from '../lib/json-utils';
-
 // === Store State ===
 
 interface TeamStoreState {