test(computation-graph): add test cases for forward propagation

- Introduced test cases to validate the forward propagation of the computation graph.
- Tested forward propagation with different input data types and shapes.
- Ensured the correct calculation of output values at each node in the computation graph during forward propagation.

Author: Mgepahmge

include/NeuZephyr/ComputeGraph.cuh

@@ -1453,6 +1453,8 @@ namespace nz::graph {
          */
         void update(Optimizer* optimizer) const;
 
+        bool inGraph(Node* node) const;
+
         /// @}
 
         /// @name File Managers

src/ComputeGraph.cu

@@ -416,6 +416,7 @@ namespace nz::graph {
             throw std::runtime_error("Graph is not sorted");
         }
         if (outputNodes.size() == 1) {
+            outputNodes[0]->output->sync();
             for (auto it = sortedNodes.rbegin(); it != sortedNodes.rend(); ++it) {
                 (*it)->backward();
             }
@@ -545,6 +546,10 @@ namespace nz::graph {
         }
     }
 
+    bool ComputeGraph::inGraph(Node* node) const {
+        return std::find(nodes.begin(), nodes.end(), node) != nodes.end();
+    }
+
     void ComputeGraph::save(const std::string& path) {
         if (path.empty()) {
             throw std::runtime_error("Path cannot be empty");