Investigate refactoring opportunities for batch management in Plugin and Compiler - review (metadata write/read)

Author: DariaMityagina

src/plugins/intel_npu/src/plugin/src/metadata.cpp

@@ -126,12 +126,10 @@ void Metadata<METADATA_VERSION_2_1>::read(const ov::Tensor& tensor) {
 void Metadata<METADATA_VERSION_2_2>::read(std::istream& stream) {
     Metadata<METADATA_VERSION_2_1>::read(stream);
 
-    int64_t batchSize;
+    std::optional<int64_t> batchSize;
     stream.read(reinterpret_cast<char*>(&batchSize), sizeof(batchSize));
 
-    if (batchSize) {
-        _batchSize = std::optional(batchSize);
-    }
+    _batchSize = batchSize;
 }
 
 void Metadata<METADATA_VERSION_2_2>::read(const ov::Tensor& tensor) {
@@ -186,9 +184,8 @@ void Metadata<METADATA_VERSION_2_1>::write(std::ostream& stream) {
 void Metadata<METADATA_VERSION_2_2>::write(std::ostream& stream) {
     Metadata<METADATA_VERSION_2_1>::write(stream);
 
-    if (_batchSize.has_value()) {
-        stream.write(reinterpret_cast<const char*>(&_batchSize), sizeof(_batchSize));
-    }
+    // _batchSize is std::optional, so either the value or std::nullopt will be written
+    stream.write(reinterpret_cast<const char*>(&_batchSize), sizeof(_batchSize));
 
     append_padding_blob_size_and_magic(stream);
 }