misc: fix issues pointed out by msvc (#7316)

* do not move constant variables

* applet_manager: avoid possible use after move

* use constant references where pointed out by msvc

* extra_hid: initialize response

* ValidateSaveState: passing slot separately is not necessary

* common: mark HashCombine as nodiscard

* cityhash: remove use of using namespace std

* Prefix all size_t with std::

done automatically by executing regex replace `([^:0-9a-zA-Z_])size_t([^0-9a-zA-Z_])` -> `$1std::size_t$2`
based on 7d8f115

* shared_memory.cpp: fix log error format

* fix compiling with pch off

src/common/thread.cpp

@@ -101,7 +101,7 @@ void SetCurrentThreadName(const char* name) {
 #elif defined(__linux__)
     // Linux limits thread names to 15 characters and will outright reject any
     // attempt to set a longer name with ERANGE.
-    std::string truncated(name, std::min(strlen(name), static_cast<size_t>(15)));
+    std::string truncated(name, std::min(strlen(name), static_cast<std::size_t>(15)));
     if (int e = pthread_setname_np(pthread_self(), truncated.c_str())) {
         errno = e;
         LOG_ERROR(Common, "Failed to set thread name to '{}': {}", truncated, GetLastErrorMsg());