feat: add OpenAI-compatible AI provider plugin with SSE streaming support

- Implemented the OpenAI-compatible AI provider plugin, including configuration, chat, and chat_stream functionalities.
- Added support for SSE streaming and tool calls.
- Integrated Boost.JSON for JSON handling.
- Created CMake configuration for the plugin.
- Added error handling and logging throughout the plugin.

dstalk_core/CMakeLists.txt

@@ -0,0 +1,51 @@
+# ============================================================
+# dstalk_core — 核心 DLL (插件宿主)
+# 包含: 插件管理 / 服务注册 / 事件总线 / 配置存储
+# ============================================================
+
+find_package(Boost REQUIRED CONFIG)
+find_package(OpenSSL REQUIRED CONFIG)
+
+# 统一的 Boost 编译宏 (header-only 模式)
+add_library(dstalk_boost_config INTERFACE)
+target_compile_definitions(dstalk_boost_config INTERFACE
+    BOOST_ALL_NO_LIB
+    BOOST_ERROR_CODE_HEADER_ONLY
+    BOOST_JSON_HEADER_ONLY
+)
+
+add_library(dstalk SHARED
+    src/host.cpp
+    src/config_store.cpp
+    src/event_bus.cpp
+    src/service_registry.cpp
+    src/plugin_loader.cpp
+    src/boost_json.cpp
+)
+
+target_include_directories(dstalk
+    PUBLIC include
+    PRIVATE src
+)
+
+target_compile_features(dstalk PUBLIC cxx_std_20)
+
+target_link_libraries(dstalk
+    PRIVATE
+        dstalk_boost_config
+        boost::boost
+        openssl::openssl
+)
+
+# dlopen / dlclose / dlsym on Linux and macOS
+if(NOT WIN32)
+    target_link_libraries(dstalk PRIVATE ${CMAKE_DL_LIBS})
+endif()
+
+# 导出 DLL 符号宏
+target_compile_definitions(dstalk
+    PRIVATE
+        DSTALK_BUILD_DLL
+    INTERFACE
+        DSTALK_USE_DLL
+)