feat: add setting for character limit of truncated deleted messages (#6491)

src/singletons/Settings.hpp

@@ -320,6 +320,13 @@ public:
         true,
     };
 
+    /// The maximum length the contents of a deleted message can be
+    /// before we truncate it in the chat
+    IntSetting deletedMessageLengthLimit = {
+        "/behaviour/deletedMessageLengthLimit",
+        50,
+    };
+
     // Auto-completion
     BoolSetting onlyFetchChattersForSmallerStreamers = {
         "/behaviour/autocompletion/onlyFetchChattersForSmallerStreamers", true};