fix(segmentation): resolve variable declaration and null check issues

* Fixed variable redeclaration in `ensureImageVolume.ts`
* Updated null checks in `getStrategyData.ts` to use more robust comparison

Author: sedghi

packages/tools/src/tools/segmentation/strategies/compositions/ensureImageVolume.ts

@@ -9,7 +9,7 @@ export default {
 
     let referencedImageIds;
     if (viewport) {
-      const referencedImageIds = viewport.getImageIds();
+      referencedImageIds = viewport.getImageIds();
       const isValidVolumeForSphere = csUtils.isValidVolume(referencedImageIds);
       if (!isValidVolumeForSphere) {
         throw new Error(

packages/tools/src/tools/segmentation/strategies/utils/getStrategyData.ts

@@ -172,9 +172,9 @@ function getStrategyData({
   strategy: unknown;
 }) {
   if (
-    ('volumeId' in operationData && operationData.volumeId !== undefined) ||
+    ('volumeId' in operationData && operationData.volumeId != null) ||
     ('referencedVolumeId' in operationData &&
-      operationData.referencedVolumeId !== undefined)
+      operationData.referencedVolumeId != null)
   ) {
     return getStrategyDataForVolumeViewport({ operationData });
   }