fix: add libsoup-3.0-dev dependency for AppImage builds

Ubuntu 22.04 needs libsoup-3.0-dev explicitly installed for Tauri v2.
While libwebkit2gtk-4.0-dev provides libsoup-2.4, Tauri requires the
newer libsoup-3.0 API.

Author: PythonTilk

.github/workflows/linux_packages.yaml

@@ -345,6 +345,8 @@ jobs:
           sudo apt-get update
 
           # Install base build dependencies
+          # Note: Ubuntu 22.04 uses libwebkit2gtk-4.0 (WebKitGTK 2.x with libsoup-2.4)
+          # but Tauri v2 requires libsoup-3.0, so we install both
           sudo apt-get install -y \
             libwebkit2gtk-4.0-dev \
             libgtk-3-dev \
@@ -361,7 +363,8 @@ jobs:
             xdg-utils \
             file \
             wget \
-            libclang-dev
+            libclang-dev \
+            libsoup-3.0-dev
 
           # Install ARM64 cross-compilation tools if needed
           if [[ "${{ matrix.target }}" == "aarch64-unknown-linux-gnu" ]]; then