refactor: Rename FastIOStd to FastIOMMap for consistency and clarity in fast I/O implementation

Author: weilycoder

test/aplusb.test.cpp

@@ -3,7 +3,7 @@
 #include "../weilycoder/fast-io.hpp"
 using namespace weilycoder;
 
-static FastIOStd<true> io;
+static FastIOMMap<true> io;
 
 int main() {
   uint64_t a = io.read_u64();

test/many_aplusb.test.cpp

@@ -3,7 +3,7 @@
 #include "../weilycoder/fast-io.hpp"
 using namespace weilycoder;
 
-static FastIOStd<> io;
+static FastIOMMap<> io;
 
 int main() {
   size_t t = io.read_u64();

weilycoder/fast-io.hpp

@@ -204,7 +204,7 @@ template <typename Reader, typename Writer, bool debug = false> struct FastIO {
 
 #if defined(__linux__) || defined(__unix__) || defined(__APPLE__)
 template <bool debug = false>
-using FastIOStd = FastIO<FastReadMMap, FastWriteFWrite<>, debug>;
+using FastIOMMap = FastIO<FastReadMMap, FastWriteFWrite<>, debug>;
 #endif
 
 template <bool debug = false>