Add commander-override echo to meta_engine verdict log

When a meta_engine candidate transitions from council_verdict to pending_commander, snapshot the verdict reasoning + axis scores + closest 3 prior commander-override decisions (by cosine similarity over override reason text from engine.db commander_overrides table). Persist snapshot to meta_engine.db verdict_echo column. Surface the 3 nearest prior overrides in the digest UI so Commander sees 'last 3 times you saw this shape, you said X' before deciding. Pure read-side feature; no mutation of verdict logic.

Commander decision latency on pending_commander queue drops (faster context recall). Commander-override consistency increases: shapes previously rejected get rejected again at higher rate (>70% match on similar-shape pairs).

Measure pending_commander queue median age before and after, over 4 weeks each. If median age does not drop ≥20%, the echo is not changing Commander's decision process and is dead weight. Also: if nearest-3 retrieval (cosine over override reasons) returns weakly related cases on a hand-graded sample of 20, retrieval is too noisy to help — kill.

Rejected by filter_score. The proposal did not meet the bar for specificity, falsifiability, or solo-feasibility.