Align the XML-RPC command stack so torrent::Object is not constructed on a 4-byte boundary.

src/command_system.cc

@@ -88,6 +88,8 @@ initialize_command_system() {
 
   CMD_ANY         ("system.file_name.replace_slash",         [](auto, auto)        { return torrent::runtime::client_config()->file_name_replace_slash(); });
   CMD_ANY_STRING_V("system.file_name.replace_slash.set",     [](auto, auto& str)   { return torrent::runtime::client_config()->set_file_name_replace_slash(str); });
+  CMD_ANY         ("system.file_name.allow_legacy_utf8",     [](auto, auto)        { return torrent::runtime::client_config()->file_name_allow_legacy_utf8(); });
+  CMD_ANY_VALUE_V ("system.file_name.allow_legacy_utf8.set", [](auto, auto& value) { return torrent::runtime::client_config()->set_file_name_allow_legacy_utf8(value); });
 
   CMD_ANY         ("system.file_status_cache.size",      [](auto, auto)      { return control->core()->file_status_cache()->size(); });
   CMD_ANY_V       ("system.file_status_cache.prune",     [](auto, auto)      { return control->core()->file_status_cache()->prune(); });
@@ -167,10 +169,13 @@ initialize_command_system() {
   rpc::rpc.mark_safe("system.time");
   rpc::rpc.mark_safe("system.time_seconds");
   rpc::rpc.mark_safe("system.time_usec");
+  rpc::rpc.mark_safe("system.torrent_name.use_sanitized");
   rpc::rpc.mark_safe("system.file.allocate");
   rpc::rpc.mark_safe("system.file.max_size");
   rpc::rpc.mark_safe("system.file.split_size");
   rpc::rpc.mark_safe("system.file.split_suffix");
+  rpc::rpc.mark_safe("system.file_name.replace_slash");
+  rpc::rpc.mark_safe("system.file_name.allow_legacy_utf8");
 
   rpc::rpc.mark_safe("system.sockets.size");
   rpc::rpc.mark_safe("system.sockets.max_size");

src/rpc/command.h

@@ -108,7 +108,7 @@ public:
 
     static stack_type* from_data(char* data) { return reinterpret_cast<stack_type*>(data); }
 
-    char buffer[sizeof(torrent::Object) * max_arguments];
+    alignas(optimal_alignment) char buffer[sizeof(torrent::Object) * max_arguments];
   };
 
   command_base() : m_copy_helper(nullptr), m_dest_helper(nullptr) {}