docs: v0.19 anticipatory coherence design (the prospective dual)

Closes the temporal coherence trinity (past via compose_resonants,
present via compute_phi, future via CoherenceForecast). Resolves U1
(anticipatory subspace selection) + U2 (substrate continuity).

Design grounded in 8 convergent literatures: Friston (predictive
coding + active inference), Mallat (wavelet MRA), Arnold/Moser (KAM
on golden ratio stability), Kleene/Curry-Howard/Martin-Lof
(realizability), Rosen (anticipatory systems), Scheffer (early-warning
signals), Robbins/Gelman (hierarchical Bayes).

5 carl-core primitives (CoherenceForecast, SubstrateState,
AnticipatoryGate, FractalForecast, realizability_gap) — the last
decided constructively in section 10 by applying the v0.19 method to
its own design. AnticipatoryReward becomes a thin studio wrapper.

4 sub-milestones: v0.19.0 (carl-core) -> v0.19.1 (studio FREE) ->
v0.19.2 (studio PAID) -> v0.19.3 (carl.camp PLATFORM). 5 idempotent
workstreams with non-overlapping file scopes.

phi-scaled bands (KAM-optimal, most-Diophantine) make MAX_DEPTH=4
derivable, not arbitrary.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: wheattoast11