VFS perf fixes, icon/stylesheet compat, download filename fix

VFS:
- Open backing fd at mo2_open time for read-only handles so mo2_read can
  splice without re-opening the file on every read call.
- Bump RLIMIT_NOFILE at mount time to fit the resulting fd pressure when
  the game keeps hundreds of BSAs open.
- Dedicated node_cache_mutex so resolveByInode / mo2_lookup stop racing
  unordered_map writes while multiple tree_mutex readers are active.
- max_read=1MB + matching conn->max_read and raised max_readahead/max_write
  so the kernel merges Wine's small sequential reads into bigger FUSE
  requests.
- Per-op wall-clock counters in mo2_init() logs so we can distinguish VFS
  latency from game-side work.

Proton launch:
- Write dxvk.conf to the prefix and set DXVK_CONFIG_FILE to force
  dxvk.enableGraphicsPipelineLibrary=False, avoiding long GPL compile
  stalls on first run.

UI / plugin compat:
- Clamp IconDelegate's per-icon width to [8, 16] so narrow content
  columns don't trigger QIcon::pixmap(0,0) returning null and logging
  "failed to load icon" every repaint.
- Pre-create lowercase symlinks in the stylesheet directory so QSS files
  authored on Windows resolve url(foo.svg) when on-disk files are Foo.svg.
- Flip content icons empty-chessboard.png and facegen.png to 8-bit RGBA
  so Qt's built-in PNG reader loads them uniformly.
- Add mobase.Version.canonicalString shim for legacy Python plugins that
  still call the old VersionInfo method on appVersion()'s return.
- BSPluginList: compare normalized plugin name lists instead of byte
  hashes so the post-run case-fix refresh stops spuriously firing the
  "load order changed" dialog.
- BSPluginList disabled by default.

Download manager:
- Parse CDN URL with QUrl + QUrlQuery and read the filename from the
  response-content-disposition query param (RFC 6266 quoted / unquoted /
  ext-value forms), not QFileInfo on the raw URL.
- When the API or URL gives us a CDN object key (no archive extension),
  prefer the actual Content-Disposition header from the live response in
  metaDataChanged and downloadFinished.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

1 files changed, 167 insertions, 0 deletions

diff --git a/libs/installer_bsplugins/src/BSPluginInfo/RecordStructureModel.cpp b/libs/installer_bsplugins/src/BSPluginInfo/RecordStructureModel.cpp
new file mode 100644
index 0000000..a28d714
--- /dev/null
+++ b/libs/installer_bsplugins/src/BSPluginInfo/RecordStructureModel.cpp
@@ -0,0 +1,167 @@
+#include "RecordStructureModel.h"
+#include "TESData/SingleRecordParser.h"
+#include "TESFile/Reader.h"
+
+#include <log.h>
+
+#include <boost/container/flat_map.hpp>
+
+namespace BSPluginInfo
+{
+
+RecordStructureModel::RecordStructureModel(TESData::PluginList* pluginList,
+                                           TESData::Record* record,
+                                           const TESData::RecordPath& path,
+                                           MOBase::IOrganizer* organizer)
+    : m_Organizer{organizer}, m_PluginList{pluginList}, m_Record{record}, m_Path{path},
+      m_Root{std::make_shared<Item>()}
+{
+  refresh();
+}
+
+void RecordStructureModel::refresh()
+{
+  boost::container::flat_map<int, const TESData::FileEntry*> entries;
+  for (const auto handle : m_Record->alternatives()) {
+    const auto entry = m_PluginList->findEntryByHandle(handle);
+    const auto info =
+        m_PluginList->getPluginByName(QString::fromStdString(entry->name()));
+    if (info && info->enabled()) {
+      entries.emplace(info->priority(), entry);
+    }
+  }
+
+  m_Files.resize(entries.size());
+
+  for (int index = static_cast<int>(entries.size()) - 1; index >= 0; --index) {
+    const auto entry = entries.nth(index)->second;
+    const auto name  = QString::fromStdString(entry->name());
+    const auto vfsEntry =
+        m_Organizer->virtualFileTree()->find(name, MOBase::FileTreeEntry::FILE);
+
+    const auto filePath = m_Organizer->resolvePath(name);
+    m_Files[index]      = QFileInfo(filePath).fileName();
+
+    readFile(m_Path, filePath, index);
+  }
+}
+
+void RecordStructureModel::readFile(const TESData::RecordPath& path,
+                                    const QString& filePath, int index)
+try {
+  const auto fileName = QFileInfo(filePath).fileName().toStdString();
+  const auto gameName = m_Organizer->managedGame()->gameName();
+  TESData::SingleRecordParser handler(gameName, path, fileName, m_Root.get(), index);
+  TESFile::Reader<TESData::SingleRecordParser> reader{};
+  reader.parse(std::filesystem::path(filePath.toStdWString()), handler);
+} catch (const std::exception& e) {
+  MOBase::log::error("Error parsing \"{}\": {}", filePath, e.what());
+}
+
+QModelIndex RecordStructureModel::index(int row, int column,
+                                        const QModelIndex& parent) const
+{
+  if (row < 0 || column < 0) {
+    return QModelIndex();
+  }
+
+  const auto parentItem = parent.isValid()
+                              ? static_cast<const Item*>(parent.internalPointer())
+                              : m_Root.get();
+  if (parentItem && row < parentItem->numChildren()) {
+    const auto childItem = parentItem->childAt(row);
+    return createIndex(row, column, childItem);
+  }
+
+  return QModelIndex();
+}
+
+QModelIndex RecordStructureModel::parent(const QModelIndex& index) const
+{
+  const auto item =
+      index.isValid() ? static_cast<const Item*>(index.internalPointer()) : nullptr;
+  const auto parentItem = item ? item->parent() : nullptr;
+  if (!parentItem) {
+    return QModelIndex();
+  }
+
+  const int row = parentItem->index();
+  return createIndex(row, 0, parentItem);
+}
+
+int RecordStructureModel::rowCount(const QModelIndex& parent) const
+{
+  const auto item = parent.isValid()
+                        ? static_cast<const Item*>(parent.internalPointer())
+                        : m_Root.get();
+  return item ? item->numChildren() : 0;
+}
+
+int RecordStructureModel::columnCount([[maybe_unused]] const QModelIndex& parent) const
+{
+  return 1 + static_cast<int>(m_Files.size());
+}
+
+QVariant RecordStructureModel::data(const QModelIndex& index, int role) const
+{
+  const auto item =
+      index.isValid() ? static_cast<const Item*>(index.internalPointer()) : nullptr;
+  if (!item) {
+    return QVariant();
+  }
+
+  switch (role) {
+  case Qt::DisplayRole:
+  case Qt::EditRole:
+    if (index.column() == 0) {
+      return item->rowHeader();
+    } else {
+      return item->displayData(index.column() - 1);
+    }
+
+  case Qt::BackgroundRole: {
+    if (index.column() == 0) {
+      return QVariant();
+    }
+
+    const int count     = columnCount() - 1;
+    const int fileIndex = index.column() - 1;
+    if (item->isLosingConflict(fileIndex, count)) {
+      return QColor(255, 0, 0, 64);
+    } else if (item->isOverriding(fileIndex)) {
+      return QColor(0, 255, 0, 64);
+    }
+
+    return QVariant();
+  }
+
+  case Qt::UserRole:
+    return QVariant::fromValue(item);
+  }
+
+  return QVariant();
+}
+
+QVariant RecordStructureModel::headerData(int section, Qt::Orientation orientation,
+                                          int role) const
+{
+  if (orientation != Qt::Horizontal)
+    return QVariant();
+
+  switch (role) {
+  case Qt::DisplayRole: {
+    if (section == 0) {
+      // Name
+      return QVariant();
+    }
+
+    if (section - 1 < m_Files.length()) {
+      return m_Files[section - 1];
+    }
+  }
+  }
+
+  return QVariant();
+}
+
+}  // namespace BSPluginInfo