fix: increased iw4 and iw5 peeking may result in a failbit in the stream

src/ZoneLoading/Loading/ZoneDataPeeking.cpp

@@ -7,12 +7,18 @@ ZoneDataPeeking::ZoneDataPeeking(std::istream& stream)
 
 void ZoneDataPeeking::PeekWithStream(const std::function<void(std::istream& stream)>& cb) const
 {
+    const auto previousBits = m_stream.rdstate();
+    // Clear any bits set previously
+    m_stream.clear();
+
     const auto previousPos = m_stream.tellg();
     m_stream.seekg(0, std::ios::beg);
 
     cb(m_stream);
 
+    m_stream.clear();
     m_stream.seekg(previousPos);
+    m_stream.setstate(previousBits);
 }
 
 void ZoneDataPeeking::EnsureHasEnoughData(const size_t size)

src/ZoneLoading/ZoneLoading.cpp

@@ -36,6 +36,9 @@ std::expected<std::unique_ptr<Zone>, std::string> ZoneLoading::LoadZone(const st
     if (!zoneLoader)
         return std::unexpected(std::format("Could not create factory for zone '{}'.", zoneName));
 
+    // We may have to clear a fail bit if the peeking resulted in eof.
+    // Otherwise, we cannot seek.
+    file.clear();
     // Revert to beginning to make sure no peeking has advanced the read position.
     // (As different peeking logic may advance by different amounts of bytes).
     file.seekg(0, std::ios::beg);