V45.38: suppress iZotope 0x7E dialog

- _is_vst2_dll: pure-Python PE export-table check (magic-aware dd offset
  PE32+112) -> IZOzone11Core.dll (runtime lib, no VSTPluginMain) dropped
  from VST2 lists in _scan_plugins and list_scan_all; plugins.py same.
- _hidden_desktop_startupinfo: scan subprocess runs on hidden desktop
  (user32 CreateDesktopW, HDESK restype) -> third-party MessageBox invisible.
- SetErrorMode(SEM_FAILCRITICALERRORS|SEM_NOOPENFILEERRORBOX) in all 4
  bridge mains: missing dependency DLL fails silently instead of blocking.

native_bridge/src/main_fx.cpp

@@ -106,6 +106,9 @@ int main(int argc, char* argv[]) {
 #ifdef _WIN32
     SetUnhandledExceptionFilter(FxCrashDumpHandler);
     AddVectoredExceptionHandler(1, FxVectoredCrashHandler);
+    // Suppress Windows loader error dialogs (plugin dependency thiếu -> 0x7E
+    // phải fail âm thầm, không MessageBox chặn user; child kế thừa error mode).
+    SetErrorMode(SEM_FAILCRITICALERRORS | SEM_NOOPENFILEERRORBOX);
     win_daemon_init();
 #endif
     // stderr, not stdout: stdout is reserved for machine-readable output in