String safety (#1548)

* Array size UB fixes

* Fix ShieldD

* Remove (almost) all unsafe strcpy calls

Bunch of macros. C arrays are easy enough and just need a different call. For various cases where a char* is passed around bare, I've made a TEXT_SPAN macro that can store a length too for bounds checking.

* Move crash handling in safe string operations to separate TU

* strcat safe version

* sprintf made safe too

* Fix compile

src/dusk/ui/editor.cpp

@@ -196,7 +196,7 @@ Rml::String get_player_name() {
     if (!has_save_data()) {
         return "";
     }
-    return dComIfGs_getPlayerName();
+    return dComIfGs_getPlayerName().buffer;
 }
 
 void set_player_name(Rml::String name) {
@@ -207,7 +207,7 @@ Rml::String get_horse_name() {
     if (!has_save_data()) {
         return "";
     }
-    return dComIfGs_getHorseName();
+    return dComIfGs_getHorseName().buffer;
 }
 
 void set_horse_name(Rml::String name) {