Replace sorting_error error code

With a new CyclicInteractionError exception class

docs/api/Doxyfile

@@ -781,7 +781,8 @@ WARN_LOGFILE           =
 # spaces. See also FILE_PATTERNS and EXTENSION_MAPPING
 # Note: If this tag is empty the current directory is searched.
 
-INPUT                  = include/loot
+INPUT                  = include/loot \
+                         include/loot/exception
 
 # This tag can be used to specify the character encoding of the source files
 # that doxygen parses. Internally doxygen uses the UTF-8 encoding. Doxygen uses

docs/api/reference.rst

@@ -43,6 +43,9 @@ Interfaces
 Classes
 =======
 
+.. doxygenclass:: loot::CyclicInteractionError
+   :members:
+
 .. doxygenclass:: loot::Error
    :members: