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

tests/desktop/swarm-skills.test.ts

@@ -428,11 +428,13 @@ describe('SkillDiscoveryEngine', () => {
     });
 
     it('toggles install status', () => {
-      engine.setSkillInstalled('code-review', false);
+      const r1 = engine.setSkillInstalled('code-review', false, { skipAutonomyCheck: true });
+      expect(r1.success).toBe(true);
       const skill = engine.getAllSkills().find(s => s.id === 'code-review');
       expect(skill!.installed).toBe(false);
 
-      engine.setSkillInstalled('code-review', true);
+      const r2 = engine.setSkillInstalled('code-review', true, { skipAutonomyCheck: true });
+      expect(r2.success).toBe(true);
       const skill2 = engine.getAllSkills().find(s => s.id === 'code-review');
       expect(skill2!.installed).toBe(true);
     });