♻️ refactor(lsp_server): move entrypoints out of named modules

- export Run() from launcher module and add non-module main TU
- apply same pattern to module-based test executables
- migrate utils/string implementation fully into string.cppm and drop string.cpp
- point clangd to linux build compilation database

lsp-server/test/test_symbol/CMakeLists.txt

@@ -18,9 +18,9 @@ endif()
 set(CMAKE_EXPERIMENTAL_CXX_MODULE_DYNDEP 1)
 
 set(SOURCES
+    main.cc
     test.cppm
     ../../src/utils/string.cppm
-    ../../src/utils/string.cpp
     ../../src/language/symbol/internal/builder.cppm
     ../../src/language/symbol/internal/store.cppm
     ../../src/language/symbol/internal/table.cppm

lsp-server/test/test_symbol/main.cc

@@ -0,0 +1,6 @@
+import lsp.test.symbol.main;
+
+int main(int argc, char* argv[])
+{
+    return Run(argc, argv);
+}

lsp-server/test/test_symbol/test.cppm

@@ -1050,7 +1050,7 @@ void AnalyzeFile(const Options& options)
 
 // ==================== 主程序 ====================
 
-int main(int argc, char* argv[])
+export int Run(int argc, char* argv[])
 {
     Options options;