feat: add AI endpoint manager plugin with configuration and routing capabilities

- Introduced `ai_endpoint_mgr` plugin to manage multiple AI provider endpoints.
- Added configuration reference documentation for `config.toml`.
- Implemented endpoint loading, active endpoint switching, and model mutation.
- Included error handling for missing endpoints and configuration failures.
- Developed unit tests covering various scenarios including error paths and concurrency.

tests/CMakeLists.txt

@@ -145,6 +145,8 @@ target_compile_definitions(dstalk_anthropic_plugin_test
         BOOST_ALL_NO_LIB
 )
 
+find_package(Boost REQUIRED CONFIG)
+
 target_link_libraries(dstalk_anthropic_plugin_test
     PRIVATE
         dstalk
@@ -174,6 +176,8 @@ target_compile_definitions(dstalk_openai_plugin_test
         BOOST_ALL_NO_LIB
 )
 
+find_package(Boost REQUIRED CONFIG)
+
 target_link_libraries(dstalk_openai_plugin_test
     PRIVATE
         dstalk
@@ -183,6 +187,37 @@ target_link_libraries(dstalk_openai_plugin_test
 
 add_test(NAME dstalk_openai_plugin_test COMMAND dstalk_openai_plugin_test)
 
+# ============================================================
+# dstalk_endpoint_mgr_plugin_test — AI endpoint manager 插件单元测试
+# 覆盖: endpoint 加载/列表脱敏/active/model 修改/路由
+# ============================================================
+
+add_executable(dstalk_endpoint_mgr_plugin_test
+    endpoint_mgr_plugin_test.cpp
+)
+
+target_include_directories(dstalk_endpoint_mgr_plugin_test
+    PRIVATE ${CMAKE_SOURCE_DIR}/dstalk_core/include
+    PRIVATE ${CMAKE_SOURCE_DIR}/plugins_upper/ai_common/include
+)
+
+target_compile_definitions(dstalk_endpoint_mgr_plugin_test
+    PRIVATE
+        BOOST_JSON_HEADER_ONLY
+        BOOST_ALL_NO_LIB
+)
+
+find_package(Boost REQUIRED CONFIG)
+
+target_link_libraries(dstalk_endpoint_mgr_plugin_test
+    PRIVATE
+        dstalk
+        ai_common
+        boost::boost
+)
+
+add_test(NAME dstalk_endpoint_mgr_plugin_test COMMAND dstalk_endpoint_mgr_plugin_test)
+
 # ============================================================
 # dstalk_network_plugin_test — Network 插件单元测试
 # W22.2 (qa-xu): 通过 #include source 访问 static 函数
@@ -203,6 +238,8 @@ target_compile_definitions(dstalk_network_plugin_test
         BOOST_ALL_NO_LIB
 )
 
+find_package(Boost REQUIRED CONFIG)
+
 target_link_libraries(dstalk_network_plugin_test
     PRIVATE
         dstalk
@@ -238,6 +275,8 @@ target_compile_features(dstalk_lsp_plugin_test
     PRIVATE cxx_std_17
 )
 
+find_package(Boost REQUIRED CONFIG)
+
 target_link_libraries(dstalk_lsp_plugin_test
     PRIVATE
         dstalk