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, 100 insertions, 0 deletions

diff --git a/libs/installer_bsplugins/src/TESData/DataItem.h b/libs/installer_bsplugins/src/TESData/DataItem.h
new file mode 100644
index 0000000..824a096
--- /dev/null
+++ b/libs/installer_bsplugins/src/TESData/DataItem.h
@@ -0,0 +1,100 @@
+#ifndef TESDATA_DATAITEM_H
+#define TESDATA_DATAITEM_H
+
+#include "TESFile/Type.h"
+
+#include <QList>
+#include <QString>
+#include <QVariant>
+
+#include <memory>
+#include <utility>
+#include <vector>
+
+namespace TESData
+{
+
+class DataItem final
+{
+public:
+  enum class ConflictType
+  {
+    Ignore,
+    BenignIfAdded,
+    Benign,
+    Override,
+    Translate,
+    NormalIgnoreEmpty,
+    Critical,
+    FormID,
+  };
+
+  DataItem() : m_Parent{nullptr} {}
+
+  DataItem(DataItem* parent, const QString& name, ConflictType conflictType)
+      : m_ConflictType{conflictType}, m_Name{name}, m_Parent{parent}
+  {}
+
+  DataItem(DataItem* parent, TESFile::Type signature, const QString& name,
+           ConflictType conflictType)
+      : m_ConflictType{conflictType}, m_Signature{signature},
+        m_Name{makeName(signature, name)}, m_Parent{parent}
+  {}
+
+  [[nodiscard]] static QString makeName(TESFile::Type signature, const QString& name);
+
+  [[nodiscard]] ConflictType conflictType() const { return m_ConflictType; }
+  [[nodiscard]] TESFile::Type signature() const { return m_Signature; }
+  [[nodiscard]] QString name() const { return m_Name; }
+  [[nodiscard]] DataItem* parent() const { return m_Parent; }
+  [[nodiscard]] int numChildren() const { return static_cast<int>(m_Children.size()); }
+  [[nodiscard]] DataItem* childAt(int index) const { return m_Children[index].get(); }
+  [[nodiscard]] int index() const { return m_Parent ? m_Parent->indexOf(this) : 0; }
+
+  [[nodiscard]] QVariant rowHeader() const { return name(); }
+
+  [[nodiscard]] QVariant data(int fileIndex) const;
+  [[nodiscard]] QVariant displayData(int fileIndex) const;
+
+  [[nodiscard]] bool isLosingConflict(int fileIndex, int fileCount) const;
+  [[nodiscard]] bool isOverriding(int fileIndex) const;
+  [[nodiscard]] bool isConflicted(int fileCount) const;
+
+  [[nodiscard]] DataItem* findChild(TESFile::Type signature) const;
+  [[nodiscard]] QVariant childData(TESFile::Type signature, int fileIndex) const;
+  [[nodiscard]] QVariant childData(const QString& name, int fileIndex) const;
+  [[nodiscard]] int indexOf(const DataItem* child) const;
+
+  template <typename... Args>
+  DataItem* insertChild(int index, Args&&... args)
+  {
+    const auto it = m_Children.insert(
+        m_Children.begin() + index,
+        std::make_shared<DataItem>(this, std::forward<Args>(args)...));
+    return it->get();
+  }
+
+  DataItem* getOrInsertChild(int index, const QString& name,
+                             ConflictType conflictType = ConflictType::Override);
+  DataItem* getOrInsertChild(int index, TESFile::Type signature, const QString& name,
+                             ConflictType conflictType = ConflictType::Override);
+
+  void setData(int fileIndex, const QVariant& data, bool caseSensitive = false);
+  void setDisplayData(int fileIndex, const QVariant& data);
+
+private:
+  [[nodiscard]] bool hasConflict(const QVariant& var1, const QVariant& var2) const;
+
+  ConflictType m_ConflictType{ConflictType::Override};
+  TESFile::Type m_Signature{};
+  bool m_CaseSensitive = false;
+  QString m_Name;
+  QList<QVariant> m_Data;
+  QList<QVariant> m_DisplayData;
+  DataItem* m_Parent;
+  std::vector<std::shared_ptr<DataItem>> m_Children;
+};
+
+}  // namespace TESData
+
+#endif  // BSPLUGININFO_DATAITEM_H