Pointwise prefix bounds imply primitive prefix-amplitude bounds #
This file is the finite, honest bridge needed by a pointwise
Siegel--Walfisz theorem. Its premise bounds every actual twisted prefix
through N; it does not assume the maximum that occurs in the conclusion.
A bound for every integer prefix, including the empty prefix at y = 0,
bounds the square root of the primitive-character prefix-square maximum.
A uniform pointwise bound for the natural-number Chebyshev twists bounds
the primitive prefix amplitude. The conversion uses Λ(0) = 0, the exact
cast from [1,y] ⊆ ℕ to [1,(y : ℤ)], and the underlying character ψ.1.
A future Siegel--Walfisz theorem uniform in every endpoint y ≤ N feeds
directly into the exact nonprincipal primitive source used by Standard BV.
The hypothesis is pointwise in y, rather than a renamed amplitude bound.