feat(blockly): Phase B1 - Register Logic Builder node

- Created IODetector utility to scan workspaces for I/O blocks
- Implemented Logic Builder runtime node with:
  - Dynamic port detection from workspace
  - Code execution context with Noodl API access
  - Signal input triggers for logic execution
  - Error handling and reporting
- Registered node in runtime and added to Custom Code category

The node should now appear in the node picker under Custom Code.
Next: Phase C - Tab system prototype

Part of TASK-012: Blockly Visual Logic Integration

packages/noodl-runtime/src/nodelibraryexport.js

@@ -581,7 +581,7 @@ function generateNodeLibrary(nodeRegister) {
       subCategories: [
         {
           name: '',
-          items: ['Expression', 'JavaScriptFunction', 'Javascript2', 'CSS Definition']
+          items: ['Expression', 'JavaScriptFunction', 'Javascript2', 'Logic Builder', 'CSS Definition']
         }
       ]
     },