Grammar of Time — GT-S1: A Common Pre-Normalised Response Cone for Quantum Records and Lorentzian Continuation

What if quantum theory and gravity appear incompatible only because we try to unite them too late? A normalised quantum state has already lost total response scale, while a spacetime metric has already interpreted public relations geometrically. GT-S1 moves the comparison one level earlier. It formulates a conditional composition theorem in which Hilbert–Born response and Lorentzian continuation arise as distinct readings of a common pre-observable process. Exact no-go results identify where this reconstruction cannot work; additional declared conditions recover universal gravito-inertial behaviour and the Einstein form as downstream selections. The paper provides a precise mathematical architecture and a falsifiable question: are quantum state and spacetime two late projections of the same deeper grammar?