chore: mark US-024 as complete and update progress log

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

prd.json

@@ -427,7 +427,7 @@
         "Verify in browser using dev-browser skill"
       ],
       "priority": 24,
-      "passes": false,
+      "passes": true,
       "notes": ""
     },
     {

progress.txt

@@ -362,3 +362,15 @@
   - Node data structure for choice: { prompt: '', options: [{ id, label }, { id, label }] }
   - React Flow nodes are draggable by default after being added to state
 ---
+
+## 2026-01-21 - US-024
+- What was implemented: Add/remove choice options functionality (2-6 options supported)
+- Files changed:
+  - src/components/editor/nodes/ChoiceNode.tsx - added addOption and removeOption callbacks, '+' button to add options, 'x' button per option to remove
+- **Learnings for future iterations:**
+  - Define MIN_OPTIONS and MAX_OPTIONS constants for clear limits
+  - Use disabled prop on buttons to enforce min/max constraints with appropriate styling (opacity-30, cursor-not-allowed)
+  - Remove button uses × character for simple cross icon
+  - Add button styled with border-dashed for visual distinction from action buttons
+  - Handles update dynamically via React Flow re-render when options array changes
+---