fix: handle UTF-8 BOM-prefixed input (#919)

Fixes https://github.com/Laupetin/OpenAssetTools/issues/771

src/Parser/Parsing/IParserLineStream.cpp

@@ -1,5 +1,13 @@
 #include "IParserLineStream.h"
 
+#include <string_view>
+
+namespace
+{
+    // A UTF-8 BOM is an encoding signature and is only valid at the start of a file.
+    constexpr std::string_view UTF8_BOM("\xEF\xBB\xBF", 3);
+} // namespace
+
 ParserLine::ParserLine()
     : m_line_number(0)
 {
@@ -10,6 +18,8 @@ ParserLine::ParserLine(std::shared_ptr<std::string> filename, const int lineNumb
       m_line_number(lineNumber),
       m_line(std::move(line))
 {
+    if (m_line_number == 1 && m_line.starts_with(UTF8_BOM))
+        m_line.erase(0, UTF8_BOM.size());
 }
 
 bool ParserLine::IsEof() const