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>

tests/CMakeLists.txt

@@ -2,6 +2,18 @@
 # tests — 单元测试
 # ============================================================
 
-# TODO: 引入测试框架后启用
-# enable_testing()
-# add_subdirectory(...)
+add_executable(dstalk-smoke-test
+    smoke_test.cpp
+)
+
+target_link_libraries(dstalk-smoke-test
+    PRIVATE dstalk
+)
+
+add_custom_command(TARGET dstalk-smoke-test POST_BUILD
+    COMMAND ${CMAKE_COMMAND} -E copy_if_different
+        $<TARGET_FILE:dstalk>
+        $<TARGET_FILE_DIR:dstalk-smoke-test>
+)
+
+add_test(NAME dstalk-smoke-test COMMAND dstalk-smoke-test)