Add `stringbuilder` package. (#4044)

* Add `stringbuilder` package.

* Fix date.

* Update xmake.lua

* Update xmake.lua

* Update xmake.lua

---------

Co-authored-by: ruki <[email protected]>

packages/s/stringbuilder/xmake.lua

@@ -0,0 +1,24 @@
+package("stringbuilder")
+    set_kind("library", {headeronly = true})
+    set_homepage("https://github.com/Isameru/stringbuilder")
+    set_description("Fast, efficient and convenient alternative to std::stringstream and std::string concatenation.")
+    set_license("MIT")
+
+    add_urls("https://github.com/Isameru/stringbuilder.git")
+    add_versions("2023.7.10", "ab772a6f0db237155d17a68c8f72b48383137872")
+
+    on_install("!windows", function (package)
+        io.replace("include/stringbuilder.h", "#pragma once", "#pragma once\n#include <ios>\n#include <stdexcept>", {plain = true})
+        io.replace("include/stringbuilder.h", "#include <intrin.h>", "", {plain = true})
+        os.cp("include", package:installdir())
+    end)
+
+    on_test(function (package)
+        assert(package:check_cxxsnippets({test = [[
+            #include <stringbuilder.h>
+            void test() {
+                auto sb = sbldr::stringbuilder<5>{};
+                sb << "123";
+            }
+        ]]}, {configs = {languages = "c++17"}}))
+    end)