WIP: auto update

deps/Sparkle/Sparkle.cmake

@@ -0,0 +1,27 @@
+# Sparkle 2 - Auto-update framework for macOS
+# https://sparkle-project.org/
+# https://github.com/sparkle-project/Sparkle
+#
+# Sparkle is distributed as a pre-built framework, so we just download and extract.
+
+if(APPLE)
+    set(SPARKLE_VERSION "2.8.1")
+
+    ExternalProject_Add(
+        dep_Sparkle
+        EXCLUDE_FROM_ALL ON
+        URL "https://github.com/sparkle-project/Sparkle/releases/download/${SPARKLE_VERSION}/Sparkle-${SPARKLE_VERSION}.tar.xz"
+        URL_HASH SHA256=5cddb7695674ef7704268f38eccaee80e3accbf19e61c1689efff5b6116d85be
+        DOWNLOAD_DIR ${DEP_DOWNLOAD_DIR}/Sparkle
+        # No build step needed - just install pre-built framework and tools
+        CONFIGURE_COMMAND ""
+        BUILD_COMMAND ""
+        INSTALL_COMMAND ${CMAKE_COMMAND} -E make_directory ${DESTDIR}/Frameworks
+        COMMAND ${CMAKE_COMMAND} -E copy_directory
+            <SOURCE_DIR>/Sparkle.framework ${DESTDIR}/Frameworks/Sparkle.framework
+        # Also install the Sparkle CLI tools (sign_update, generate_appcast) for CI/CD signing
+        COMMAND ${CMAKE_COMMAND} -E make_directory ${DESTDIR}/bin
+        COMMAND ${CMAKE_COMMAND} -E copy <SOURCE_DIR>/bin/sign_update ${DESTDIR}/bin/sign_update
+        COMMAND ${CMAKE_COMMAND} -E copy <SOURCE_DIR>/bin/generate_appcast ${DESTDIR}/bin/generate_appcast
+    )
+endif()