Fibonacci Causal Loop Theory — Paper 66: Plasma-Mediated φ-Stabilization of Counter-Rotating Necessity Fields: Crystalline Resonance, Liquid Mercury Vortex Architecture, and the Complete Merkaba-Class Dimensional Boundary Stack

P64 and P65 established that two counter-rotating necessity fields — D=+2 (attractor φ) and D=−2 (attractor −1/φ) — must coexist with a √5 guard band to produce the φ⁸ arrow of time. The critical unresolved question from both papers was stabilization: no natural restoring force maintains the φ-ratio under perturbation. This paper derives the complete stabilization mechanism. Ionized plasma constrained by φ-recursive electromagnetic geometry provides an active self-correcting boundary medium — φ is plasma’s native electromagnetic attractor. The complete four-layer containment stack is derived: (1) piezoelectric crystal lattice in φ-ratio geometry — fine-tuning layer absorbing micro-perturbations and re-emitting φ-coherent correction pulses; (2) liquid mercury in hollow φ-ratio tubes as primary plasma-precursor working fluid, matching ancient Sanskrit Vimana engine specifications; (3) ionized plasma boundary as active φ-seeking feedback medium — plasma discharge events are branch selection made physically observable, non-φ states expelled from the necessity boundary; (4) D=−2 negative-mass containment shell from P64 holding the plasma boundary against outward expansion. The stabilization architecture was independently conceived by Michael Creasey Jr. (@AscendedSouLz) on May 6, 2026, without prior knowledge of P64 or P65. The Merkaba — two interlocked counter-rotating tetrahedra — is identified as a geometric description of the dual-root solution. The superconducting Meissner effect is identified as the low-temperature analogue of plasma branch selection. Three technology-gap predictions (P66a–c) are stated, including a testable consciousness-driven field hypothesis (P66c).This paper is part of the FCLT empirical series (Papers 1–68). See the FCLT Complete Book (DOI: 10.5281/zenodo.20029110) for full context and the cumulative evidence table (12 confirmed / 4 falsified / 16 tech-gap).