A universal survival front for close-in exoplanets from summed tidal and thermal hazards

We present a survival-front framework for the close-in inner edge of exoplanet systems. The observed innermost-survivor boundary is modeled as the projected trace of a critical surface $H(q,L_\star,M_\star)=1$ in periapsis-luminosity-mass space, with dimensionless headroom coordinates $X$ and $Y$ that organize irradiation and tidal hazards through temperature-ratio and density-ratio constructions. In these variables, the edge is described by a minimal additive hazard law $H=X^{-2}+Y^{-3}$, producing a connected front with tidal, radiative, and crossover regimes. The manuscript develops the geometric interpretation of the front, the soft-knee structure, orthogonal depletion width, universal host-rescaled collapse, and an operational ranking of systems nearest the critical boundary. Working technical preprint. This Zenodo record is a timestamped public disclosure of the integrated framework, derivations, figures, and current benchmark analysis prior to a later arXiv posting. The present version contains the complete current research outline and technical development; presentation and some quantitative details may be refined in subsequent versions.