docs: save complete SESSION_STATE for next session

- Document AI non-determinism finding (critical discovery)
- Record ImageAdjustmentModal completion
- Detail integration checklist for next session
- Explain new user-controlled image adjustment workflow
- All commits and features documented for continuity

dev_docs/SESSION_STATE.md

@@ -64,7 +64,72 @@ Test Image 1 (IMG_6188):
 2. If pattern confirmed, the updated prompt should improve future detections
 3. Track which item types (cables, drives, modules) have detection issues
 
-**Status:** ✅ **COMPLETE & DEBUGGED** — Debug panel working, AI prompt improved based on findings
+---
+
+## SESSION 32 SUMMARY — ImageAdjustmentModal & AI Non-Determinism Discovery
+
+### Critical Finding: AI Model Inconsistency
+Same image (300GB HDD) uploaded 3 times produced different AI results:
+
+**Test 5**: Rotation -162°, Crop (1350, 550) 1550×2150
+**Test 6**: Rotation -106°, Crop (1390, 190) 1440×2580  
+**Test 7**: Rotation +162°, Crop (1350, 650) 1450×1750
+
+**Variance Analysis**:
+- Rotation: -162° to +162° (324° swing, 56° between tests)
+- Crop Y: 190-650 (460px variance)
+- Crop Height: 1750-2580 (830px variance)
+- Confidence: Always 0.98 (misleading - doesn't reflect actual accuracy)
+
+**Conclusion**: Gemini Vision is **non-deterministic** - even identical images produce different results. This is NOT a prompt issue, but a fundamental limitation of the AI model.
+
+### Solution Implemented: User-Controlled Image Adjustment
+
+**New Component: ImageAdjustmentModal** (`frontend/components/ImageAdjustmentModal.tsx`)
+- Shows original image after item save
+- User can adjust before final save
+- Features:
+  - Rotation: Slider (-180° to +180°) + Gesture rotation
+  - Zoom: Scroll wheel (desktop) + Pinch (trackpad/mobile) + Slider
+  - Pan: Drag to move image around canvas
+  - Crop: Preset aspect ratios (16:9, 4:3, 1:1, 9:16, Free)
+  - Touch: Full mobile support (pinch zoom, drag pan)
+  - Checkbox: "Use this image" (default ON)
+  - Reset: Button to revert to original state
+
+**Canvas Features**:
+- 800×600px preview
+- Real-time rotation/zoom/pan
+- Transformation-aware rendering
+- Touch event handling for mobile
+
+### Flow Design (Ready for Integration)
+1. User captures photo → AI extracts data
+2. User reviews extracted fields in onboarding modal
+3. User clicks "Save Item" → **Text data saved to DB**
+4. **ImageAdjustmentModal pops up** with original image
+5. User adjusts rotation/crop as needed
+6. User confirms checkbox ("Use this image" ON by default)
+7. **Adjusted image processed & saved** with item
+8. Item finalized
+
+### Integration Checklist (For Next Session)
+- [ ] Import ImageAdjustmentModal in AIOnboarding/create item flow
+- [ ] Add state to track: `showImageAdjustment`, `originalImageBlob`
+- [ ] After "Save Item" API call succeeds → show modal
+- [ ] Pass original image to modal
+- [ ] Handle modal confirm → apply rotation/crop → compress → save
+- [ ] Handle modal cancel → discard image
+- [ ] Update item's `photo_path`, `photo_thumbnail_path` after adjustment
+- [ ] Test full E2E flow with test image
+
+### Key Integration Points
+1. **AIOnboarding.tsx**: Add modal state, pass image
+2. **ImageAdjustmentModal.tsx**: Already created (ready to use)
+3. **Image Processing**: May need new backend endpoint to apply rotation/crop/compress post-adjustment
+4. **Database**: Item already has photo fields, just need to populate after modal
+
+**Status:** ✅ **COMPONENT COMPLETE** — ImageAdjustmentModal ready for integration. AI non-determinism resolved with user-controlled workflow
 
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