server: avoid splitting stream after final listpack

Skip PushToConsumerIfNeeded after the last listpack in SaveStreamObject.
The stream metadata tail (length, IDs, consumer groups) must stay
bundled with the last listpack chunk so the loader can read it in the
same chunk.

Author: abhijat

src/server/rdb_save.cc

@@ -572,7 +572,11 @@ error_code RdbSerializer::SaveStreamObject(const PrimeValue& pv) {
     RETURN_ON_ERR(SaveString((uint8_t*)ri.key, ri.key_len));
     RETURN_ON_ERR(SaveString(lp, lp_bytes));
 
-    PushToConsumerIfNeeded(FlushState::kFlushMidEntry);
+    // Do not split after the final listpack. The loader can resume between listpacks,
+    // but the stream metadata tail is expected to stay bundled with the last listpack chunk, not
+    // in its own separate chunk.
+    if (i + 1 < rax_size)
+      PushToConsumerIfNeeded(FlushState::kFlushMidEntry);
   }
 
   std::move(stop_listpacks_rax).Invoke();