FDEP-TP framework — Article A1: Conceptual and physiological foundations (Lancet Diabetes & Endocrinology submission package)

Submission package for Article A1 of the FDEP-TP trilogy (Lancet Diabetes & Endocrinology). Contains the Lancet-format manuscript (.docx and .pdf, 14 pp), Quarto source, cover letter, four display items (DI1-DI4) at 300 dpi, refs_A1.bib (30 cited references), the numerical ledger with eigenfunction loadings table, and the F1-F9 verification report. Article A1 reports the conceptual and physiological layer of the FDEP-TP framework: four conceptual moves (the periprandial transition as the unit of analysis; physiologic periprandial responsiveness as the operational construct; weight as a contextual modifier; the non-obese-without-T2D cohort as the reference distribution) and the physiological reading of the four leading multivariate functional principal component eigenfunctions of the joint enteropancreatic operator (Psi_1 distal L-cell dominance with PYY total integrated squared L^2-norm 0.762 and secondary integrated incretin contribution 0.211; Psi_2 proximal-versus-distal entero-endocrine sequencing along the small bowel; Psi_3 biphasic glucose-insulin coupling; Psi_4 ghrelin tone with sleeve-gastrectomy signature). Pre-registered ecological proof-of-concept analysis at the cohort-time-arm level (OSF DOI 10.17605/OSF.IO/3CZRE; v10.0 protocol frozen 2026-04-22): 23 source studies, 71 (Author x Cohort) tuples, 55 productive cohort-time-arms, 2,750 pseudo-subjects across 7 canonical cohorts (non-obese-without-T2D reference, obesity, T2DM, obesity+T2DM, caloric restriction, sleeve gastrectomy, Roux-en-Y gastric bypass) and 11 analyte forms (master_table.csv SHA-256 2829cd78018e411783671ec00f849647858bda552cfa4ec23ad505ba9704a117). The joint Happ-Greven operator on the 9-analyte panel retained K=12 components at the Golovkine 2025 multivariate-FVE >= 0.90 threshold (cumulative 92%; N/K=29.2). Pillai trace on the joint score panel (n=350) yielded omnibus F=18.29 with Post-CR F=52.09; subject-level bootstrap stability >= 80% per cohort. Companion paper A2 (mathematical-statistical layer; Zenodo v2.0-A2) and A3 (procedural-translational layer; forthcoming) complete the trilogy.