Part II: The 4+1 Sector Template
The organisational blueprint for all downstream books is derived, not assumed. The five generators of τ induce four primitive sectors (α, π, γ, η) plus one mixed sector (ω-coupling)—the 4+1 template.
Langlands_0 (boundary functoriality) induces this decomposition: the functor from boundary characters to interior holomorphic data preserves sector structure, so the 4+1 form is a functorial consequence. At the first enrichment level E₁, the template instantiates as electromagnetism, weak, strong, gravity, plus Higgs/mass—but the derivation of physical content is strictly deferred to Books IV and V. The Parity Bridge Theorem identifies the weak sector as the canonical carrier for the computational bootstrap (bridge to Book VI), and the No Knobs Principle establishes that all sector couplings are determined by ι_τ, not free parameters.