Are you saying Picard is trimming your songs? Because I ditto many other commenters; Picard has never trimmed any of my songs.
My flow back when I used to self-host was (1) get the songs -> (2) tag the songs with Picard, which also renames the files automatically -> (3) place appropriately in my Navidrome server. I know people like to automate acquisition with various arr projects, but I liked curating my library manually.