Add missing javascriptcoregtk-4.1-dev to build dependencies

- Added libjavascriptcoregtk-4.1-dev for Ubuntu/Debian
- Added javascriptcore-gtk-devel for Fedora/RHEL
- Fixes build error: javascriptcore-rs-sys v1.1.1 requires javascriptcoregtk-4.1.pc
- This completes the Tauri/webkit dependencies for desktop builds

src/07-gbapp/building.md

@@ -94,6 +94,7 @@ sudo apt install -y \
     libglib2.0-dev \
     libgtk-3-dev \
     libwebkit2gtk-4.0-dev \
+    libjavascriptcoregtk-4.1-dev \
     libayatana-appindicator3-dev \
     librsvg2-dev
 ```
@@ -137,6 +138,7 @@ sudo dnf install -y \
     gobject-introspection-devel \
     gtk3-devel \
     webkit2gtk3-devel \
+    javascriptcore-gtk-devel \
     libappindicator-gtk3-devel \
     librsvg2-devel
 ```