cmake: enable package manager support with install/export targets

Author: ZZBaron

CMakeLists.txt

@@ -1,5 +1,4 @@
 cmake_minimum_required(VERSION 3.20)
-
 project(ImGuiFileDialog)
 
 add_library(ImGuiFileDialog STATIC
@@ -8,8 +7,37 @@ add_library(ImGuiFileDialog STATIC
     ImGuiFileDialogConfig.h
 )
 
-target_include_directories(ImGuiFileDialog PUBLIC ${CMAKE_CURRENT_SOURCE_DIR})
+# Use generator expressions for proper include directory handling
+target_include_directories(ImGuiFileDialog
+    PUBLIC
+        $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}>
+        $<INSTALL_INTERFACE:include>
+)
 
 if(UNIX)
     target_compile_options(ImGuiFileDialog PUBLIC -Wno-unknown-pragmas)
 endif()
+
+# Installation configuration
+include(GNUInstallDirs)
+
+# Install the library
+install(TARGETS ImGuiFileDialog
+    EXPORT ImGuiFileDialogTargets
+    ARCHIVE DESTINATION ${CMAKE_INSTALL_LIBDIR}
+    LIBRARY DESTINATION ${CMAKE_INSTALL_LIBDIR}
+    RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR}
+)
+
+# Install headers
+install(FILES 
+    ImGuiFileDialog.h 
+    ImGuiFileDialogConfig.h
+    DESTINATION ${CMAKE_INSTALL_INCLUDEDIR}
+)
+
+# Install export targets
+install(EXPORT ImGuiFileDialogTargets
+    FILE ImGuiFileDialogConfig.cmake
+    DESTINATION ${CMAKE_INSTALL_LIBDIR}/cmake/ImGuiFileDialog
+)