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, 85 insertions, 0 deletions

diff --git a/libs/installer_bsplugins/src/GUI/selectiondialog.ui b/libs/installer_bsplugins/src/GUI/selectiondialog.ui
new file mode 100644
index 0000000..9b7f7e3
--- /dev/null
+++ b/libs/installer_bsplugins/src/GUI/selectiondialog.ui
@@ -0,0 +1,85 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<ui version="4.0">
+ <class>SelectionDialog</class>
+ <widget class="QDialog" name="SelectionDialog">
+  <property name="geometry">
+   <rect>
+    <x>0</x>
+    <y>0</y>
+    <width>527</width>
+    <height>327</height>
+   </rect>
+  </property>
+  <property name="windowTitle">
+   <string>Select</string>
+  </property>
+  <layout class="QVBoxLayout" name="verticalLayout">
+   <property name="spacing">
+    <number>20</number>
+   </property>
+   <item>
+    <widget class="QLabel" name="descriptionLabel">
+     <property name="text">
+      <string>Placeholder</string>
+     </property>
+     <property name="wordWrap">
+      <bool>true</bool>
+     </property>
+    </widget>
+   </item>
+   <item>
+    <widget class="QScrollArea" name="scrollArea">
+     <property name="horizontalScrollBarPolicy">
+      <enum>Qt::ScrollBarAlwaysOff</enum>
+     </property>
+     <property name="widgetResizable">
+      <bool>true</bool>
+     </property>
+     <widget class="QWidget" name="scrollAreaWidgetContents">
+      <property name="geometry">
+       <rect>
+        <x>0</x>
+        <y>0</y>
+        <width>503</width>
+        <height>219</height>
+       </rect>
+      </property>
+      <layout class="QVBoxLayout" name="verticalLayout_2">
+       <property name="margin">
+        <number>0</number>
+       </property>
+       <item>
+        <widget class="QDialogButtonBox" name="buttonBox">
+         <property name="sizePolicy">
+          <sizepolicy hsizetype="Expanding" vsizetype="Expanding">
+           <horstretch>0</horstretch>
+           <verstretch>0</verstretch>
+          </sizepolicy>
+         </property>
+         <property name="orientation">
+          <enum>Qt::Vertical</enum>
+         </property>
+         <property name="standardButtons">
+          <set>QDialogButtonBox::NoButton</set>
+         </property>
+         <property name="centerButtons">
+          <bool>false</bool>
+         </property>
+        </widget>
+       </item>
+      </layout>
+     </widget>
+    </widget>
+   </item>
+   <item>
+    <widget class="QPushButton" name="cancelButton">
+     <property name="text">
+      <string>Cancel</string>
+     </property>
+    </widget>
+   </item>
+  </layout>
+ </widget>
+ <resources/>
+ <connections/>
+</ui>