Sealed prediction: PMNS sin theta_13 from golden-ratio flavor mechanism

Sealed prediction file (plaintext) for the PMNS neutrino mixing angle θ13. Embargoed until 2030-12-01, on which date the file is automatically released by Zenodo. The Universal Compression Theory (UCT) golden-ratio flavor mechanism predicts sinθ13 = 1/φ4 = 0.14589803, equivalent to sin²θ13 = 0.02129 and θ13 = 8.388°. Currently measured (PDG 2024): sin²θ13 = 0.0220 ± 0.0007 (1.0σ deviation from prediction). Decisive resolution expected from JUNO (operations 2026-2027) and DUNE (2028-2030). Cross-references the encrypted (AES-256-CBC + PBKDF2) version on the master record (pmns_theta13_prediction.json.aes, encrypted SHA-256: ce4b9bce38be488f02df65cd1420807c61fff53bd4f7768ac850963401c4a765). Both layers — embargo and encryption — prevent post-hoc adjustment. Master record: 10.5281/zenodo.20113359.