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, 24 insertions, 2 deletions

diff --git a/libs/esptk/src/espfile.cpp b/libs/esptk/src/espfile.cpp
index b97d222..a88398d 100644
--- a/libs/esptk/src/espfile.cpp
+++ b/libs/esptk/src/espfile.cpp
@@ -17,8 +17,30 @@ ESP::File::File(const std::wstring& fileName)
 #ifdef _WIN32
   m_File.open(fileName, std::fstream::in | std::fstream::binary);
 #else
-  // Linux: convert wstring to string (UTF-8)
-  std::string narrowName(fileName.begin(), fileName.end());
+  // Linux: properly encode wstring → UTF-8. The old naive
+  // `string(w.begin(), w.end())` copy truncated any codepoint > 0x7F
+  // (e.g. ö U+00F6, – U+2013) which broke paths like "Mörskom Estate" or
+  // "Official Master Files – Cleaned".
+  std::string narrowName;
+  narrowName.reserve(fileName.size());
+  for (wchar_t wc : fileName) {
+    const auto cp = static_cast<uint32_t>(wc);
+    if (cp < 0x80) {
+      narrowName.push_back(static_cast<char>(cp));
+    } else if (cp < 0x800) {
+      narrowName.push_back(static_cast<char>(0xC0 | (cp >> 6)));
+      narrowName.push_back(static_cast<char>(0x80 | (cp & 0x3F)));
+    } else if (cp < 0x10000) {
+      narrowName.push_back(static_cast<char>(0xE0 | (cp >> 12)));
+      narrowName.push_back(static_cast<char>(0x80 | ((cp >> 6) & 0x3F)));
+      narrowName.push_back(static_cast<char>(0x80 | (cp & 0x3F)));
+    } else {
+      narrowName.push_back(static_cast<char>(0xF0 | (cp >> 18)));
+      narrowName.push_back(static_cast<char>(0x80 | ((cp >> 12) & 0x3F)));
+      narrowName.push_back(static_cast<char>(0x80 | ((cp >> 6) & 0x3F)));
+      narrowName.push_back(static_cast<char>(0x80 | (cp & 0x3F)));
+    }
+  }
   m_File.open(narrowName, std::fstream::in | std::fstream::binary);
 #endif
   init();