feat(blockly): Phase A foundation - Blockly setup, custom blocks, and generators

- Install blockly package (~500KB)
- Create BlocklyWorkspace React component with serialization
- Define custom Noodl blocks (Input/Output, Variables, Objects, Arrays)
- Implement JavaScript code generators for all custom blocks
- Add theme-aware styling for Blockly workspace
- Export initialization functions for easy integration

Part of TASK-012: Blockly Visual Logic Integration

packages/noodl-editor/package.json

@@ -74,6 +74,7 @@
     "algoliasearch": "^5.35.0",
     "archiver": "^5.3.2",
     "async": "^3.2.6",
+    "blockly": "^12.3.1",
     "classnames": "^2.5.1",
     "dagre": "^0.8.5",
     "diff3": "0.0.4",