feat: Added shortcut to switch between providers

lib/libimhex/source/api/imhex_api.cpp

@@ -255,6 +255,10 @@ namespace hex {
             }
         }
 
+        i64 getCurrentProviderIndex() {
+            return s_currentProvider;
+        }
+
         bool isValid() {
             return !s_providers.empty() && s_currentProvider >= 0 && s_currentProvider < i64(s_providers.size());
         }