You conveniently ignored the fact that it is in the gemara (no matter the terminology) according to some rishonim and the p’sak of the Rema, even though putting in the wheat before Shabbos is not a violation of the issur melocho.
So tell me, if you ignore the gemara and claim there is no precedent, why do you think so many poskim made up a “new” concept of zilzul Shabbos?