fix: avoid bank update in VBLoRAAdapter ctor

Author: ooples

src/LoRA/Adapters/VBLoRAAdapter.cs

@@ -311,6 +311,9 @@ public VBLoRAAdapter(
         {
             _bankIndicesB = GenerateRandomIndices(rank, bankSizeB);
         }
+
+        // Now that banks + indices are initialized, sync the underlying LoRA layer to the selected vectors.
+        UpdateLoRALayerFromBanks(_loraLayer);
     }
 
     /// <summary>
@@ -406,16 +409,13 @@ private int[] GenerateRandomIndices(int count, int maxValue)
     /// </remarks>
     protected override LoRALayer<T> CreateLoRALayer(int rank, double alpha)
     {
-        // Create a standard LoRA layer - we'll override its matrices with bank-selected vectors
         int inputSize = GetInputShape()[0];
         int outputSize = GetOutputShape()[0];
 
-        LoRALayer<T> loraLayer = new LoRALayer<T>(inputSize, outputSize, rank, alpha);
-
-        // Replace the LoRA layer's matrices with bank-selected vectors
-        UpdateLoRALayerFromBanks(loraLayer);
-
-        return loraLayer;
+        // Important: this virtual is invoked from the base constructor, before VB-LoRA banks/indices are initialized.
+        // We therefore only construct a standard LoRA layer here and let the derived constructor/Forward() synchronize
+        // it with the vector banks once initialization is complete.
+        return new LoRALayer<T>(inputSize, outputSize, rank, alpha);
     }
 
     /// <summary>