refactor asset serving & fix typos

- Added necessary libraries for Linux build in build-linux.yml
- Updated submodule reference for zupdater
- Added new video resource for wireless gallery import
- use UDID instead of UUID across multiple files
- Improved user interface messages and layout in various widgets
- Refactor http server

resources.qrc

@@ -64,5 +64,6 @@
         <file>resources/ipad-mockups/ipad.png</file>
         <file>resources/DeveloperDiskImages.json</file>
         <file>resources/keychain.mp4</file>
+        <file>resources/wireless-gallery-import.mp4</file>
     </qresource>
 </RCC>