sync: Agent Architecture Overhaul - AI SDK 6 + workflow optimization

Synced from private repo (feature/ai-sdk-6-upgrade):
- Upgrade AI SDK 5 → 6 (packages + API changes)
- Add sqliteQuery tool for flexible read-only queries
- New WorkflowExecutor with workflow-specific tools
- 83% token reduction for workflow execution
- Remove mini-rah dead code (simplified architecture)
- Add context management usage endpoint
- Fix Connect workflow instructions
- Clickable node references in workflow UI

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

src/components/helpers/NodeLabelRenderer.tsx

@@ -45,7 +45,7 @@ function NodeLabel({ id, title, dimensions, onNodeClick }: NodeLabelProps) {
           verticalAlign: 'baseline'
         }}
       >
-        #{id}
+        {id}
       </span>
       {/* Non-clickable title - bold and underlined */}
       <span style={{