Fix array.init_elem to use source offset when reading segment data

The interpreter's visitArrayInitElem was ignoring the source offset
parameter when reading from the element segment. It used seg->data[i]
instead of seg->data[offsetVal + i], meaning it always read from the
beginning of the segment regardless of the specified offset.

The offset was already correctly computed and used in the bounds check,
but not in the actual data access loop. This is now consistent with how
visitArrayInitData handles its offset parameter.

Author: sumleo

src/wasm-interpreter.h

@@ -4597,7 +4597,8 @@ class ModuleRunnerBase : public ExpressionRunner<SubType> {
       // of references in the table! ArrayNew suffers the same problem.
       // Fixing it will require changing how we represent segments, at least
       // in the interpreter.
-      data->values[indexVal + i] = self()->visit(seg->data[i]).getSingleValue();
+      data->values[indexVal + i] =
+        self()->visit(seg->data[offsetVal + i]).getSingleValue();
     }
     return {};
   }