Fix Flatpak build: Add required application icons

- Created PNG icons from existing icon.ico in multiple sizes (64x64, 128x128)
- Updated Flatpak manifest to install icons in standard hicolor locations
- Added Icon field to desktop entry file
- Resolves appstreamcli 'gui-app-without-icon' error
- Flatpak build now has all required components for successful packaging

Author: yammanhammad

flatpak/org.routeplanner.RoutePlanner.yml

@@ -34,10 +34,15 @@ modules:
         Name=Route Planner
         Comment=Delivery Route Optimizer
         Exec=route-planner
+        Icon=org.routeplanner.RoutePlanner
         Terminal=false
         Type=Application
         Categories=Office;Utility;
         EOF
+      - mkdir -p /app/share/icons/hicolor/64x64/apps
+      - mkdir -p /app/share/icons/hicolor/128x128/apps
+      - cp icons/org.routeplanner.RoutePlanner-64.png /app/share/icons/hicolor/64x64/apps/org.routeplanner.RoutePlanner.png
+      - cp icons/org.routeplanner.RoutePlanner-128.png /app/share/icons/hicolor/128x128/apps/org.routeplanner.RoutePlanner.png
       - mkdir -p /app/share/metainfo
       - |
         cat > /app/share/metainfo/org.routeplanner.RoutePlanner.metainfo.xml << 'EOF'