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, 88 insertions, 0 deletions

diff --git a/libs/installer_bsplugins/src/MOPlugin/Settings.h b/libs/installer_bsplugins/src/MOPlugin/Settings.h
new file mode 100644
index 0000000..cf93a29
--- /dev/null
+++ b/libs/installer_bsplugins/src/MOPlugin/Settings.h
@@ -0,0 +1,88 @@
+#ifndef SETTINGS_H
+#define SETTINGS_H
+
+#include "GUI/IGeometrySettings.h"
+#include "GUI/IStateSettings.h"
+
+#include <expanderwidget.h>
+#include <imoinfo.h>
+#include <lootcli/lootcli.h>
+
+#include <boost/signals2.hpp>
+
+#include <QColor>
+#include <QDialog>
+#include <QHeaderView>
+#include <QSettings>
+#include <QSplitter>
+#include <QTreeView>
+
+class Settings final : public GUI::IGeometrySettings<QDialog>,
+                       public GUI::IStateSettings<QHeaderView>,
+                       public GUI::IStateSettings<QSplitter>,
+                       public GUI::IStateSettings<MOBase::ExpanderWidget>
+{
+public:
+  using SignalSettingChanged =
+      boost::signals2::signal<void(const QString&, const QVariant&, const QVariant&)>;
+
+  static void init(MOBase::IOrganizer* organizer);
+
+  [[nodiscard]] static Settings* instance();
+
+  void set(const QString& setting, const QVariant& value);
+
+  [[nodiscard]] QVariant get(const QString& setting, const QVariant& def) const;
+
+  template <typename T>
+  [[nodiscard]] T get(const QString& setting, const QVariant& def) const
+  {
+    return get(setting, def).value<T>();
+  }
+
+  bool onSettingChanged(const std::function<void(const QString&, const QVariant&,
+                                                 const QVariant&)>& func);
+
+  [[nodiscard]] QColor overwrittenLooseFilesColor() const;
+  [[nodiscard]] QColor overwritingLooseFilesColor() const;
+  [[nodiscard]] QColor overwrittenArchiveFilesColor() const;
+  [[nodiscard]] QColor overwritingArchiveFilesColor() const;
+  [[nodiscard]] QColor containedColor() const;
+  [[nodiscard]] bool offlineMode() const;
+  [[nodiscard]] lootcli::LogLevels lootLogLevel() const;
+
+  [[nodiscard]] bool externalChangeWarning() const;
+  [[nodiscard]] bool enableSortButton() const;
+  [[nodiscard]] bool lootShowDirty() const;
+  [[nodiscard]] bool lootShowMessages() const;
+  [[nodiscard]] bool lootShowProblems() const;
+
+  void saveTreeExpandState(const QTreeView* view);
+  void restoreTreeExpandState(QTreeView* view) const;
+
+  void saveState(const QHeaderView* header) override;
+  void restoreState(QHeaderView* header) const override;
+
+  void saveState(const QSplitter* splitter) override;
+  void restoreState(QSplitter* splitter) const override;
+
+  void saveState(const MOBase::ExpanderWidget* expander) override;
+  void restoreState(MOBase::ExpanderWidget* expander) const override;
+
+  // IGeometrySettings<QDialog>
+
+  void saveGeometry(const QDialog* dialog) override;
+  void restoreGeometry(QDialog* dialog) const override;
+
+private:
+  void onPluginSettingChanged(const QString& pluginName, const QString& key,
+                              const QVariant& oldValue, const QVariant& newValue);
+
+  explicit Settings(MOBase::IOrganizer* organizer);
+
+  MOBase::IOrganizer* Organizer;
+  QSettings MOSettings;
+  SignalSettingChanged SettingChanged;
+};
+
+#endif  // SETTINGS_H