refactor(frontend): remove two pieces of unreachable code

frontend/src/app/workspace/component/hugging-face-image-upload/hugging-face-image-upload.component.html

@@ -32,7 +32,7 @@
       [src]="previewSrc"
       alt="Uploaded Hugging Face task input" />
     <div class="hf-image-meta">
-      <span>{{ displayFileName || "Selected image" }}</span>
+      <span>{{ displayFileName }}</span>
       <button
         nz-button
         nzSize="small"

frontend/src/app/workspace/component/hugging-face-image-upload/hugging-face-image-upload.component.spec.ts

@@ -200,6 +200,34 @@ describe("HuggingFaceImageUploadComponent", () => {
     });
   });
 
+  describe("rendered preview label", () => {
+    const previewLabel = () => fixture.nativeElement.querySelector(".hf-image-meta span") as HTMLElement | null;
+
+    it("labels the preview 'Uploaded image' when an image has no filename", () => {
+      component.formControl.setValue("data:image/jpeg;base64,AAA");
+      fixture.detectChanges();
+
+      expect(previewLabel()?.textContent?.trim()).toBe("Uploaded image");
+    });
+
+    it("labels the preview with the filename once one is known", () => {
+      component.formControl.setValue("data:image/jpeg;base64,AAA");
+      component.fileName = "cat.jpg";
+      fixture.detectChanges();
+
+      expect(previewLabel()?.textContent?.trim()).toBe("cat.jpg");
+    });
+
+    it("renders no preview at all without an image, so the label is never empty", () => {
+      // The preview only renders while previewSrc is non-empty, which happens exactly
+      // when hasImage is true — and displayFileName is never empty in that case.
+      component.formControl.setValue("");
+      fixture.detectChanges();
+
+      expect(previewLabel()).toBeNull();
+    });
+  });
+
   // ── Shared mocking helpers ──────────────────────────────────────────────
   // These helpers let us drive the private compressImage / renderCompressedDataUrl
   // pipeline end-to-end through onFileSelected.

frontend/src/app/workspace/service/drag-drop/drag-drop.service.spec.ts

@@ -467,6 +467,30 @@ describe("DragDropService", () => {
       expect(() => (dragDropService as any).clearEdgeIntersectionHighlight(link)).not.toThrow();
       expect((dragDropService as any).findIntersectedLink({ x: 0, y: 0 })).toBeNull();
     });
+
+    it("skips links that are in the Texera graph but have no model in the JointJS paper", () => {
+      const workflowActionService: WorkflowActionService = TestBed.inject(WorkflowActionService);
+      const paperHost = document.createElement("div");
+      document.body.appendChild(paperHost);
+      try {
+        workflowActionService.getJointGraphWrapper().attachMainJointPaper({ el: paperHost });
+        // findIntersectedLink walks the Texera graph but resolves each link against the
+        // JointJS paper, and the two can diverge. A link known only to Texera resolves to
+        // no joint model, so it must be skipped rather than dereferenced.
+        vi.spyOn(workflowActionService.getTexeraGraph(), "getAllLinks").mockReturnValue([
+          {
+            linkID: "ghost",
+            source: { operatorID: "op-a", portID: "op-a-output-0" },
+            target: { operatorID: "op-b", portID: "op-b-input-0" },
+          },
+        ] as OperatorLink[]);
+
+        expect(() => (dragDropService as any).findIntersectedLink({ x: 0, y: 0 })).not.toThrow();
+        expect((dragDropService as any).findIntersectedLink({ x: 0, y: 0 })).toBeNull();
+      } finally {
+        document.body.removeChild(paperHost);
+      }
+    });
   });
 
   describe("handleOperatorRecommendationOnDrag (drag lifecycle)", () => {

frontend/src/app/workspace/service/drag-drop/drag-drop.service.ts

@@ -440,10 +440,6 @@ export class DragDropService {
 
     for (const link of allLinks) {
       const jointLink = paper.getModelById(link.linkID) as joint.dia.Link;
-      if (!jointLink) {
-        continue;
-      }
-
       const linkView = paper.findViewByModel(jointLink) as joint.dia.LinkView;
       if (!linkView) {
         continue;