TQNT-V5.17 — Two-stage cascade reheating: resolution of the V5.16 BBN tension

TQNT-V5.17 provides the complete resolution of the V5.16 internal Treh/BBN tension via a two-stage cascade reheating mechanism, with NO new free parameter. Mechanism: Stage 1: χ → 01 (unknot, Jones polynomial = 1) — NO αEMcn Vassiliev suppression because the unknot carries cn = 0. Stage 2: primordial photons thermalise into the SM bath via standard QED interactions. Results (parameter-free): Treh = 2.53 × 1015 GeV — a factor 2.5 × 1018 above the BBN lower bound. Ne = 50.5 e-folds — well inside the Planck window [50, 65]. ns = 0.9604, consistent with Planck at -1.06σ. r = 4.7 × 10−3, BICEP/Keck margin × 13. Validation: 21/21 V5.17 tests + 25/25 V5.16 non-regression tests = 46/46 passing. Zero new free parameter introduced. Complements the V5 monograph (10.5281/zenodo.19131538) and closes the V5.14/V5.15/V5.16/V5.17 inflation-to-reheating sequence.