fix(lite): "Open data folder" points to the actual lite wallet dir

The lite SilentDragonXLite backend stores its wallet in its own directory
(dirs::data_dir()/silentdragonxlite — %APPDATA%\silentdragonxlite on Windows,
~/.silentdragonxlite on Linux, ~/Library/Application Support/silentdragonxlite on
macOS), NOT the full-node getDragonXDataDir() (…/Hush/DRAGONX). The newly added
lite "Open data folder" button opened the wrong (full-node) directory.

Add Platform::getLiteWalletDataDir() mirroring the backend's get_zcash_data_path
for the "main" chain, and point the lite button at it. The full-node button is
unchanged.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

src/util/platform.cpp

@@ -219,6 +219,24 @@ std::string Platform::getDataDir()
     return getDragonXDataDir();
 }
 
+std::string Platform::getLiteWalletDataDir()
+{
+    // Mirror the SilentDragonXLite backend's get_zcash_data_path() for the "main" chain:
+    //   Windows/macOS: dirs::data_dir()/silentdragonxlite   (data_dir = %APPDATA%, ~/Library/App Support)
+    //   Linux:         ~/.silentdragonxlite
+#ifdef _WIN32
+    char path[MAX_PATH];
+    if (SUCCEEDED(SHGetFolderPathA(nullptr, CSIDL_APPDATA, nullptr, 0, path))) {
+        return std::string(path) + "\\silentdragonxlite\\";
+    }
+    return getHomeDir() + "\\AppData\\Roaming\\silentdragonxlite\\";
+#elif defined(__APPLE__)
+    return getHomeDir() + "/Library/Application Support/silentdragonxlite/";
+#else
+    return getHomeDir() + "/.silentdragonxlite/";
+#endif
+}
+
 std::string Platform::getConfigDir()
 {
 #ifdef _WIN32