feat: PDB import via RawPDB, no msdia140.dll dependency

Replace DIA SDK COM-based PDB importer with RawPDB (MolecularMatters)
which reads PDB files directly via memory-mapped I/O. Adds File menu
"Import PDB..." dialog with type filtering, selection, and progress.

- Vendor raw_pdb into third_party/
- Two-phase API: enumeratePdbTypes() + importPdbSelected()
- Full recursive import of structs/unions/arrays/pointers/bitfields
- PDB import dialog with name filter, select-all, type count
- Benchmark: 1654 types from ntkrnlmp.pdb in 16ms
- Reorganize import/export files into src/imports/

third_party/raw_pdb/src/PDB_IPIStream.cpp

@@ -0,0 +1,140 @@
+// Copyright 2011-2022, Molecular Matters GmbH <office@molecular-matters.com>
+// See LICENSE.txt for licensing details (2-clause BSD License: https://opensource.org/licenses/BSD-2-Clause)
+
+#include "PDB_PCH.h"
+#include "PDB_IPIStream.h"
+#include "PDB_RawFile.h"
+#include "PDB_Util.h"
+#include "PDB_DirectMSFStream.h"
+#include "PDB_InfoStream.h"
+#include "Foundation/PDB_Memory.h"
+
+namespace
+{
+	// the IPI stream always resides at index 4
+	static constexpr const uint32_t IPIStreamIndex = 4u;
+}
+
+
+// ------------------------------------------------------------------------------------------------
+// ------------------------------------------------------------------------------------------------
+PDB::IPIStream::IPIStream(void) PDB_NO_EXCEPT
+	: m_header()
+	, m_stream()
+	, m_records(nullptr)
+	, m_recordCount(0u)
+{
+}
+
+
+// ------------------------------------------------------------------------------------------------
+// ------------------------------------------------------------------------------------------------
+PDB::IPIStream::IPIStream(IPIStream&& other) PDB_NO_EXCEPT
+	: m_header(PDB_MOVE(other.m_header))
+	, m_stream(PDB_MOVE(other.m_stream))
+	, m_records(PDB_MOVE(other.m_records))
+	, m_recordCount(PDB_MOVE(other.m_recordCount))
+{
+	other.m_records = nullptr;
+	other.m_recordCount = 0u;
+}
+
+
+// ------------------------------------------------------------------------------------------------
+// ------------------------------------------------------------------------------------------------
+PDB::IPIStream& PDB::IPIStream::operator=(IPIStream&& other) PDB_NO_EXCEPT
+{
+	if (this != &other)
+	{
+		PDB_DELETE_ARRAY(m_records);
+
+		m_header = PDB_MOVE(other.m_header);
+		m_stream = PDB_MOVE(other.m_stream);
+		m_records = PDB_MOVE(other.m_records);
+		m_recordCount = PDB_MOVE(other.m_recordCount);
+
+		other.m_records = nullptr;
+		other.m_recordCount = 0u;
+	}
+
+	return *this;
+}
+
+
+// ------------------------------------------------------------------------------------------------
+// ------------------------------------------------------------------------------------------------
+PDB::IPIStream::IPIStream(const RawFile& file, const IPI::StreamHeader& header) PDB_NO_EXCEPT
+	: m_header(header)
+	, m_stream(file.CreateMSFStream<CoalescedMSFStream>(IPIStreamIndex))
+	, m_records(nullptr)
+	, m_recordCount(GetLastTypeIndex() - GetFirstTypeIndex())
+{
+	// types in the IPI stream are accessed by their index from other streams.
+	// however, the index is not stored with types in the IPI stream directly, but has to be built while walking the stream.
+	// similarly, because types are variable-length records, there are no direct offsets to access individual types.
+	// we therefore walk the IPI stream once, and store pointers to the records for trivial O(N) array lookup by index later.
+	m_records = PDB_NEW_ARRAY(const CodeView::IPI::Record*, m_recordCount);
+
+	// ignore the stream's header
+	size_t offset = sizeof(IPI::StreamHeader);
+
+	// parse the CodeView records
+	uint32_t typeIndex = 0u;
+	while (offset < m_stream.GetSize())
+	{
+		// https://llvm.org/docs/PDB/CodeViewTypes.html
+		const CodeView::IPI::Record* record = m_stream.GetDataAtOffset<const CodeView::IPI::Record>(offset);
+		const uint32_t recordSize = GetCodeViewRecordSize(record);
+		m_records[typeIndex] = record;
+
+		// position the stream offset at the next record
+		offset += sizeof(CodeView::IPI::RecordHeader) + recordSize;
+
+		++typeIndex;
+	}
+}
+
+
+// ------------------------------------------------------------------------------------------------
+// ------------------------------------------------------------------------------------------------
+PDB::IPIStream::~IPIStream(void) PDB_NO_EXCEPT
+{
+	PDB_DELETE_ARRAY(m_records);
+}
+
+
+// ------------------------------------------------------------------------------------------------
+// ------------------------------------------------------------------------------------------------
+PDB_NO_DISCARD PDB::ErrorCode PDB::HasValidIPIStream(const RawFile& file) PDB_NO_EXCEPT
+{
+	const PDB::InfoStream infoStream(file);
+	if (!infoStream.HasIPIStream())
+	{
+		return ErrorCode::InvalidStream;
+	}
+
+	DirectMSFStream stream = file.CreateMSFStream<DirectMSFStream>(IPIStreamIndex);
+	if (stream.GetSize() < sizeof(IPI::StreamHeader))
+	{
+		return ErrorCode::InvalidStream;
+	}
+
+	const IPI::StreamHeader header = stream.ReadAtOffset<IPI::StreamHeader>(0u);
+	if (header.version != IPI::StreamHeader::Version::V80)
+	{
+		return ErrorCode::UnknownVersion;
+	}
+
+	return ErrorCode::Success;
+}
+
+
+// ------------------------------------------------------------------------------------------------
+// ------------------------------------------------------------------------------------------------
+PDB_NO_DISCARD PDB::IPIStream PDB::CreateIPIStream(const RawFile& file) PDB_NO_EXCEPT
+{
+	DirectMSFStream stream = file.CreateMSFStream<DirectMSFStream>(IPIStreamIndex);
+
+	const IPI::StreamHeader header = stream.ReadAtOffset<IPI::StreamHeader>(0u);
+	return IPIStream { file, header };
+}