perf(startup): stat dragonxd instead of reading it for the update offer

On Windows every full-node launch read the whole installed dragonxd.exe
(about 16.7 MB) on the UI thread and byte-scanned it for a version
string, to decide whether to offer the bundled node, which only needs
whether the file exists and its size. getInstalledDaemonInfo() takes a
scanVersion flag, and the update offer now only stats the file.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/app.cpp

@@ -4298,7 +4298,7 @@ void App::maybeOfferDaemonUpdate()
 {
     if (!supportsFullNodeLifecycleActions()) return;   // lite / no embedded-daemon build
     if (capture_mode_ || !settings_) return;           // never during a UI sweep
-    auto inst = resources::getInstalledDaemonInfo();
+    auto inst = resources::getInstalledDaemonInfo(/*scanVersion=*/false);   // only exists/size are used here
     auto bun  = resources::getBundledDaemonInfo();
     // Only when a daemon is ALREADY installed and its size differs from the bundled one — an absent
     // daemon is extracted normally, and a same-size match needs nothing. Fire once per bundled