Wrong custos direction handling in tied notes

Hello, 

Thank you for the amazing Lilypond. 


I have been advised (on IRC) to post a bug about custodes I found. 
Here is a minimal example 


%%%%%%%%%%%%%%%%% 
%%% A custos shows where the next note will be and is placed at the end of a staff. 
%%% It usually works fine. 
%%% 
%%% But, the custos should point up when the second note on the next staff is higher than the first. 
%%% This doesn't happen if the last note is tied to the first note on the next staff. 


\version "2.24.3" 
\score { 
{ 
a'1 ~ 
\break 
a' 
g 
} 
\layout { 
\context { 
\Staff 
\consists Custos_engraver 
\override Custos.style = #'mensural 
} 
} 
} 
%%%%%%%%%%%%%%%%% 


Suggested fix: a command like \custosUp to manually set or adjust the direction of the custos. 
Doc for custodes : 
http://lilypond.org/doc/v2.24/Documentation/notation/ancient-notation-_002d-common-features#custodes 
https://lilypond.org/doc/v2.24/Documentation/internals/custos 

Thank you ! 
-- 
Alan