Add Linux desktop file installation and update CPack configuration

- Add element.desktop.in template with CMake variable substitution
- Configure and install desktop file to /usr/share/applications
- Install icon to freedesktop.org standard location
- Update Debian package dependencies with X11 libraries
- Add libjack-jackd2-0, fonts-roboto, libxrender1, libxcomposite1
- Improve CPack configuration with cleaner system naming
- Add installer target to clean CPack staging directories

Author: mfisher31

CMakeLists.txt

@@ -202,21 +202,38 @@ set(CPACK_PACKAGE_INSTALL_DIRECTORY "Element")
 set(CPACK_RESOURCE_FILE_README "${CMAKE_CURRENT_SOURCE_DIR}/data/intro.txt")
 set(CPACK_RESOURCE_FILE_LICENSE "${CMAKE_CURRENT_SOURCE_DIR}/LICENSES/GPL3.txt")
 
+string(TOLOWER "${CMAKE_SYSTEM_PROCESSOR}" ELEMENT_PROCESSOR)
+
 if(LINUX)
-    set(CPACK_GENERATOR "TGZ;STGZ;DEB")
+    set(ELEMENT_SYSTEM_NAME "linux")
+    set(CPACK_GENERATOR "DEB")
+    set(CPACK_PACKAGE_NAME "element")
     set(CPACK_ARCHIVE_COMPONENT_INSTALL OFF)
     set(CPACK_PACKAGING_INSTALL_PREFIX "${CMAKE_INSTALL_PREFIX}")
-    set(CPACK_DEBIAN_PACKAGE_DEPENDS "libasound2;libfreetype6;libx11-6;libxext6;libxrandr2;libxinerama1;libxcursor1;libcurl4;libgl1;libstdc++6")
+    set(CPACK_DEBIAN_PACKAGE_DEPENDS "libasound2;libjack-jackd2-0;fonts-roboto;libfreetype6;libx11-6;libxext6;libxrandr2;libxinerama1;libxcursor1;libxrender1;libxcomposite1;libcurl4;libgl1;libstdc++6")
 elseif(APPLE)
+    set(ELEMENT_SYSTEM_NAME "macos")
+    set(ELEMENT_PROCESSOR "universal")
     set(CPACK_GENERATOR "ZIP")
     set(CPACK_ARCHIVE_COMPONENT_INSTALL OFF)
     set(CPACK_SET_DESTDIR OFF)
     set(CPACK_PACKAGING_INSTALL_PREFIX "/")
 else()
+    set(ELEMENT_SYSTEM_NAME "windows")
     set(CPACK_GENERATOR "ZIP")
     set(CPACK_ARCHIVE_COMPONENT_INSTALL OFF)
     set(CPACK_PACKAGING_INSTALL_PREFIX "/")
 endif()
 
-set(CPACK_PACKAGE_FILE_NAME "${CPACK_PACKAGE_NAME}-${CPACK_PACKAGE_VERSION}-${CMAKE_SYSTEM_NAME}-${CMAKE_SYSTEM_PROCESSOR}")
+set(ELEMENT_GENERATOR ${CPACK_GENERATOR})
+set(CPACK_PACKAGE_FILE_NAME "${PROJECT_NAME}-${CPACK_PACKAGE_VERSION}-${ELEMENT_SYSTEM_NAME}-${ELEMENT_PROCESSOR}")
 include(CPack)
+
+# Clean CPack staging directory before and after packaging to prevent macOS relocation issues
+add_custom_target(installer
+    COMMAND ${CMAKE_COMMAND} -E rm -rf "${PROJECT_BINARY_DIR}/_CPack_Packages"
+    COMMAND ${CMAKE_COMMAND} --build "${PROJECT_BINARY_DIR}" --target package
+    COMMAND ${CMAKE_COMMAND} -E rm -rf "${PROJECT_BINARY_DIR}/_CPack_Packages"
+    COMMENT "Cleaning CPack staging and building package"
+    VERBATIM
+    USES_TERMINAL)

data/CMakeLists.txt

@@ -6,3 +6,24 @@ juce_add_binary_data(element-binarydata
     HEADER_NAME binarydata.hpp 
     NAMESPACE element::res
     SOURCES ${ELEMENT_RES})
+
+# Linux desktop file and icon installation
+if(UNIX AND NOT APPLE)
+    # Configure desktop file with CMake variables
+    configure_file(
+        ${CMAKE_CURRENT_SOURCE_DIR}/element.desktop.in
+        ${CMAKE_CURRENT_BINARY_DIR}/element.desktop
+        @ONLY
+    )
+
+    # Install desktop file
+    install(FILES ${CMAKE_CURRENT_BINARY_DIR}/element.desktop
+        DESTINATION ${CMAKE_INSTALL_DATADIR}/applications
+    )
+
+    # Install icon
+    install(FILES ${CMAKE_CURRENT_SOURCE_DIR}/images/icon.png
+        DESTINATION ${CMAKE_INSTALL_DATADIR}/icons/hicolor/512x512/apps
+        RENAME element.png
+    )
+endif()

data/element.desktop.in

@@ -0,0 +1,13 @@
+[Desktop Entry]
+Version=1.0
+Type=Application
+Name=Element
+GenericName=Audio Plugin Host
+Comment=Audio Plugin Host and Modular Instrument (v@PROJECT_VERSION_FULL@)
+Exec=@CMAKE_INSTALL_PREFIX@/@CMAKE_INSTALL_BINDIR@/element
+Icon=element
+Terminal=false
+Categories=AudioVideo;Audio;Midi;Sequencer;
+MimeType=application/x-element-session;application/x-element-graph;
+Keywords=audio;midi;plugin;host;daw;vst;lv2;
+StartupNotify=true