Add shift key support for reference cursors and update button text

dicom-viewer/src/App.tsx

@@ -1118,6 +1118,7 @@ function App({ container_id, imageStacks, autoCacheStack, annotationJson, viewer
   }, []);
 
   const [altPressed, setAltPressed] = useState(false);
+  const [shiftPressed, setShiftPressed] = useState(false);
 
   useEffect(() => {
     const mainToolGroup = ToolGroupManager.getToolGroup(MAIN_TOOL_GROUP_ID);
@@ -1144,23 +1145,32 @@ function App({ container_id, imageStacks, autoCacheStack, annotationJson, viewer
   useEffect(() => {
     const handleKeyDown = (e: KeyboardEvent) => {
       if (e.altKey) setAltPressed(true);
+      if (e.shiftKey) setShiftPressed(true);
     };
     const handleKeyUp = (e: KeyboardEvent) => {
       if (!e.altKey) setAltPressed(false);
+      if (!e.shiftKey) setShiftPressed(false);
+    };
+    const handleBlur = () => {
+      setAltPressed(false);
+      setShiftPressed(false);
     };
     window.addEventListener("keydown", handleKeyDown);
     window.addEventListener("keyup", handleKeyUp);
+    window.addEventListener("blur", handleBlur);
     return () => {
       window.removeEventListener("keydown", handleKeyDown);
       window.removeEventListener("keyup", handleKeyUp);
+      window.removeEventListener("blur", handleBlur);
     };
   }, []);
 
   useEffect(() => {
-    if (!altEnablesReferenceCursors) return;
     const mainToolGroup = ToolGroupManager.getToolGroup(MAIN_TOOL_GROUP_ID);
     if (!mainToolGroup) return;
-    if (altPressed) {
+    const modifierActive = shiftPressed || (altEnablesReferenceCursors && altPressed);
+
+    if (modifierActive) {
       if (!mainToolGroup.hasTool(ReferenceCursors.toolName)) {
         mainToolGroup.addTool(ReferenceCursors.toolName);
       }
@@ -1171,7 +1181,7 @@ function App({ container_id, imageStacks, autoCacheStack, annotationJson, viewer
         mainToolGroup.setToolDisabled(ReferenceCursors.toolName);
       }
     }
-  }, [altPressed, altEnablesReferenceCursors]);
+  }, [altPressed, shiftPressed, altEnablesReferenceCursors]);
 
   // Helper to apply all mouse tool bindings (normal or ctrl)
   const applyMouseToolBindings = useCallback(() => {
@@ -4111,8 +4121,8 @@ function App({ container_id, imageStacks, autoCacheStack, annotationJson, viewer
                 onClick={() => setAltEnablesReferenceCursors((prev) => !prev)}
               >
                 {altEnablesReferenceCursors
-                  ? "Disable Alt Key for Reference Cursors"
-                  : "Enable Alt Key for Reference Cursors"}
+                  ? "Disable Alt Key for Reference Cursors (Shift always works)"
+                  : "Enable Alt Key for Reference Cursors (Shift always works)"}
               </button>
               <button
                 style={{