refactor: move YYCC_U8 from reinterpret.hpp to string.hpp

- move YYCC_U8 def.
- create shared template in testbench.

testbench/CMakeLists.txt

@@ -15,6 +15,14 @@ PRIVATE
     yycc/patch/contains.cpp
     yycc/patch/starts_ends_with.cpp
 )
+target_sources(YYCCTestbench
+PRIVATE
+FILE_SET HEADERS
+FILES
+    shared/parse_template.hpp
+    shared/stringify_template.hpp
+    shared/utf_literal.hpp
+)
 # Setup headers
 target_include_directories(YYCCTestbench
 PUBLIC

testbench/yycc/constraint/builder.cpp

@@ -1,7 +1,6 @@
 #include <gtest/gtest.h>
 #include <yycc.hpp>
 #include <yycc/constraint/builder.hpp>
-#include <yycc/string/reinterpret.hpp>
 
 #include <yycc/prelude/rust.hpp>
 

testbench/yycc/num/parse.cpp

@@ -1,7 +1,6 @@
 #include <gtest/gtest.h>
 #include <yycc.hpp>
 #include <yycc/num/parse.hpp>
-#include <yycc/string/reinterpret.hpp>
 
 #include <yycc/prelude/rust.hpp>
 

testbench/yycc/num/stringify.cpp

@@ -1,7 +1,6 @@
 #include <gtest/gtest.h>
 #include <yycc.hpp>
 #include <yycc/num/stringify.hpp>
-#include <yycc/string/reinterpret.hpp>
 
 #include <yycc/prelude/rust.hpp>
 

testbench/yycc/string/op.cpp

@@ -1,7 +1,6 @@
 #include <gtest/gtest.h>
 #include <yycc.hpp>
 #include <yycc/string/op.hpp>
-#include <yycc/string/reinterpret.hpp>
 
 #include <yycc/prelude/core.hpp>