docs: update task-3 builder exploration notes

Week-1/Task-3/thob/notes.md

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+# Builder Exploration Notes — Task 3: Hover Interaction
+
+## Capability Gap Identified
+
+- **Hover Events**: No visible support for `onPointerOver` / `onPointerOut` (hover) in the interaction panel
+- **Click Behavior**: `onClick` trigger is present in UI, but actions did not produce visible results during testing
+- **Visual Logic**: No clear way to connect user interaction to visual state changes (e.g., color/scale)
+- **Interaction Experience**: Scene appears static due to lack of responsive feedback
+
+---
+
+## Observations
+
+- Interaction UI exists but execution behavior is unclear or inconsistent
+- Hover-based interaction is not exposed as a first-class concept
+- Click interaction may require additional configuration or may be unstable in current environment
+
+---
+
+## Comparison vs Code
+
+- **Vanilla**:
+  - Requires raycasting and mouse tracking
+  - Fully controllable but complex
+
+- **R3F**:
+  - Hover interaction is simple using `onPointerOver` / `onPointerOut`
+  - Very intuitive and minimal code
+
+- **Thob**:
+  - Hover interaction not available
+  - Click interaction present but did not behave as expected during testing
+
+---
+
+## Key Insight
+
+The builder currently lacks clear support for continuous pointer-based interactions (like hover) and shows limitations in reliably executing event-based visual updates.
+
+---
+
+## Product Perspective
+
+Hover interactions are essential for user feedback (highlighting, selection cues). The absence or instability of such interactions limits the builder’s ability to create engaging 3D experiences.
+
+---
+
+## Verdict
+
+Strong for **static visual setup**  
+Limited for **interactive behavior (hover and dynamic feedback)**