SVG preview fitting size problem solved

tests/layout-ui-wiring.test.js

@@ -33,16 +33,6 @@ assert(
   'Build Layout should use the backend svg_url response'
 );
 assert(
-<<<<<<< HEAD
-  canvasHtml.includes('result.svg_ready && result.svg_url') &&
-    canvasHtml.includes('buildLayoutRequestRef') &&
-    canvasHtml.includes('buildLayoutBusyRef') &&
-    canvasHtml.includes("cache: 'no-store'"),
-  'Build Layout should wait for a ready, versioned SVG response and prevent stale duplicate preview updates'
-);
-assert(
-=======
->>>>>>> jingwen_main
   canvasHtml.includes('result.preview_error') &&
     canvasHtml.includes('Preview skipped: '),
   'Build Layout should log when the backend saves YAML but skips SVG preview because the router stack is unavailable'
@@ -60,8 +50,18 @@ assert(
   'layout SVG preview should expose an editable scale value'
 );
 assert(
-  canvasHtml.includes('objectFit: \'contain\''),
-  '100% layout preview scale should fit the full SVG within the screen'
+  canvasHtml.includes('objectFit: \'contain\'') &&
+    canvasHtml.includes('previewCanvasRef') &&
+    canvasHtml.includes('ResizeObserver') &&
+    canvasHtml.includes('svgSize') &&
+    canvasHtml.includes('naturalWidth') &&
+    canvasHtml.includes('naturalHeight') &&
+    canvasHtml.includes('const fitScalePercent = clampLayoutScale(Math.floor') &&
+    canvasHtml.includes('layoutScale ?? fitScalePercent') &&
+    canvasHtml.includes('const stageWidth = baseWidth * normalizedScale / 100') &&
+    !canvasHtml.includes('useState(100)') &&
+    !canvasHtml.includes('baseWidth * fitScale * normalizedScale / 100'),
+  'layout preview should default to the actual fitted SVG scale percent instead of redefining 100% as fit'
 );
 assert(
   canvasHtml.includes('className="build-gds-btn"'),
@@ -354,7 +354,7 @@ assert(
     canvasHtml.includes('layoutBounds') &&
     canvasHtml.includes('stageWidth') &&
     canvasHtml.includes('stageHeight'),
-  'layout preview should mouse-wheel zoom and size 100% from calculated box_size layout bounds'
+  'layout preview should mouse-wheel zoom from the actual calculated SVG scale'
 );
 assert(
   canvasHtml.includes('reactFlowInstance.fitBounds') &&