Complete build wiring and CLI file commands

Align documented commands with the CLI, enable optional GUI/test targets, and remove committed API secrets so the project is safer to build and run.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

dstalk-gui/CMakeLists.txt

@@ -13,3 +13,9 @@ target_link_libraries(dstalk-gui
         dstalk
         SDL3::SDL3
 )
+
+add_custom_command(TARGET dstalk-gui POST_BUILD
+    COMMAND ${CMAKE_COMMAND} -E copy_if_different
+        $<TARGET_FILE:dstalk>
+        $<TARGET_FILE_DIR:dstalk-gui>
+)

dstalk-gui/src/main.cpp

@@ -35,7 +35,6 @@ int main(int argc, char* argv[])
         return 1;
     }
 
-    /* TODO: 主循环 — SDL 事件处理, UI 渲染, 调用 dstalk_chat */
     bool running = true;
     SDL_Event event;
     while (running) {