feat(desktop): pipeline result preview + industry templates + onboarding auto-trigger

Sprint 2: 产品体验打磨 + 行业模板

- Create PipelineResultPreview component with tab-based output switching
- Connect workflow/hand messages to PresentationContainer in ChatArea
- Add auto-trigger first Hand after onboarding (industry-specific queries)
- Seed 3 industry agent templates (education, healthcare, design-shantou)

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

desktop/src/App.tsx

@@ -357,6 +357,26 @@ function App() {
       time: '',
     });
     setShowOnboarding(false);
+
+    // Auto-trigger first Hand based on industry template
+    const templateId = clone.source_template_id || '';
+    const industryQueries: Record<string, { hand: string; action: string; query: string }> = {
+      'edu-teacher-001': { hand: 'researcher', action: 'report', query: '帮我研究2026年教育数字化转型趋势，包括AI教学工具的最新进展' },
+      'healthcare-admin-001': { hand: 'collector', action: 'collect', query: '帮我采集最新的医疗政策文件摘要，重点关注基层医疗改革方向' },
+      'design-shantou-001': { hand: 'researcher', action: 'report', query: '帮我研究2026年服装设计流行趋势，包括色彩、面料和款式创新' },
+    };
+    const task = industryQueries[templateId];
+    if (task) {
+      // Delay slightly to let UI settle
+      setTimeout(() => {
+        useHandStore.getState().triggerHand(task.hand, {
+          action: task.action,
+          query: { query: task.query },
+        }).catch(() => {
+          // Non-critical — user can trigger manually
+        });
+      }, 2000);
+    }
   };
 
   // 处理主视图切换