candidate_04 — Working-set bridge to localvm (reduced scope)

Assigned by Phase 4 (research/candidate_ranking.md). Core gaps: G24 (+G09).

First falsifier: domain-conditioned block-ablation working sets on a 3B model; < 10% reduction vs global working set kills per-domain prefetching.

Status: assigned — prototyping starts after the mandatory substrate (expH capture-cost frontier, expA/expD noise floors, map-cards v0). Hypothesis will be registered in hypothesis.md before any run (charter §10).