feat: switch text to UTF-8; add Unicode key events, dead keys & Czech layout; fix numpad navigation; add NumLock support

programs/include/montauk/statuscodes.h

@@ -56,27 +56,28 @@ inline const char* GetStatusText(StatusCode statusCode) {
     }
 }
 
+// Shared with C (libc.c), so no nullptr.
 inline const char* GetStatusExplanationText(StatusCode statusCode) {
     const char* explanationText[] = {
-        nullptr, // 0
-        nullptr, // 1
-        nullptr, // 2
-        nullptr, // 3
+        0, // 0
+        0, // 1
+        0, // 2
+        0, // 3
         "The path is protected by the system and cannot be modified.", // 4
-        nullptr, // 5
-        nullptr, // 6
-        nullptr, // 7
-        nullptr, // 8
-        nullptr, // 9
-        nullptr, // 10
-        nullptr, // 11
-        nullptr, // 12
+        0, // 5
+        0, // 6
+        0, // 7
+        0, // 8
+        0, // 9
+        0, // 10
+        0, // 11
+        0, // 12
         "The buffer supplied by the caller is too small.", // 13
-        nullptr, // 14
+        0, // 14
     };
 
     if (statusCode > 0 && statusCode <= 14) {
-        if (explanationText[statusCode] != nullptr) {
+        if (explanationText[statusCode] != 0) {
             return explanationText[statusCode];
         }
     }