fix: resolve crop tool regression with stale ref and aspect ratio minSize (refs #120)

Three bugs fixed in the draw-first crop tool introduced by PR #114:

1. Stale cropAreaRef: replaced useEffect-based ref sync with direct
   synchronous updates in handleMove and handleDrawStart. The useEffect
   ran after browser paint, so handleDragEnd read stale values (often
   {width:0, height:0}), preventing cropDrawn from being set.

2. Aspect ratio minSize: when aspectRatio=6 (VIN mode), height=width/6
   required width>=60% to pass the height>=10% check. Now only checks
   width>=minSize when aspect ratio constrains height.

3. Bounds clamping: aspect-ratio-forced height could push crop area
   past 100% of container. Now clamps y position to keep within bounds.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

frontend/src/shared/components/CameraCapture/useImageCrop.ts

@@ -95,10 +95,6 @@ export function useImageCrop(options: UseImageCropOptions = {}): UseImageCropRet
   const drawOriginRef = useRef({ x: 0, y: 0 });
   const cropAreaRef = useRef(cropArea);
 
-  useEffect(() => {
-    cropAreaRef.current = cropArea;
-  }, [cropArea]);
-
   const setCropArea = useCallback(
     (area: CropArea) => {
       setCropAreaState(getAspectRatioAdjustedCrop(area));
@@ -177,7 +173,9 @@ export function useImageCrop(options: UseImageCropOptions = {}): UseImageCropRet
       startPosRef.current = { x: clientX, y: clientY };
       drawOriginRef.current = { x, y };
 
-      setCropAreaState({ x, y, width: 0, height: 0 });
+      const initial = { x, y, width: 0, height: 0 };
+      setCropAreaState(initial);
+      cropAreaRef.current = initial;
 
       isDrawingRef.current = true;
       activeHandleRef.current = null;
@@ -203,18 +201,24 @@ export function useImageCrop(options: UseImageCropOptions = {}): UseImageCropRet
         const originX = drawOriginRef.current.x;
         const originY = drawOriginRef.current.y;
 
-        let newCrop: CropArea = {
+        const drawnWidth = Math.abs(currentX - originX);
+        const drawnHeight = aspectRatio
+          ? drawnWidth / aspectRatio
+          : Math.abs(currentY - originY);
+        let drawnY = Math.min(originY, currentY);
+        // Clamp so crop doesn't exceed container bounds when aspect ratio forces height
+        if (aspectRatio && drawnY + drawnHeight > 100) {
+          drawnY = Math.max(0, 100 - drawnHeight);
+        }
+        const newCrop: CropArea = {
           x: Math.min(originX, currentX),
-          y: Math.min(originY, currentY),
+          y: drawnY,
-          width: Math.abs(currentX - originX),
+          width: drawnWidth,
-          height: Math.abs(currentY - originY),
+          height: drawnHeight,
         };
 
-        if (aspectRatio) {
-          newCrop.height = newCrop.width / aspectRatio;
-        }
-
         setCropAreaState(newCrop);
+        cropAreaRef.current = newCrop;
         return;
       }
 
@@ -303,7 +307,9 @@ export function useImageCrop(options: UseImageCropOptions = {}): UseImageCropRet
           break;
       }
 
-      setCropAreaState(constrainCrop(newCrop));
+      const constrained = constrainCrop(newCrop);
+      setCropAreaState(constrained);
+      cropAreaRef.current = constrained;
     },
     [isDragging, constrainCrop, aspectRatio]
   );
@@ -312,13 +318,17 @@ export function useImageCrop(options: UseImageCropOptions = {}): UseImageCropRet
     if (isDrawingRef.current) {
       isDrawingRef.current = false;
       const area = cropAreaRef.current;
-      if (area.width >= minSize && area.height >= minSize) {
+      // When aspect ratio constrains one dimension, only check the free dimension
+      const meetsMinSize = aspectRatio
+        ? area.width >= minSize
+        : area.width >= minSize && area.height >= minSize;
+      if (meetsMinSize) {
         setCropDrawn(true);
       }
     }
     activeHandleRef.current = null;
     setIsDragging(false);
-  }, [minSize]);
+  }, [minSize, aspectRatio]);
 
   // Add global event listeners for drag
   useEffect(() => {