Problem

In crates/zeph-mcp/src/manager.rs (lines ~583-591 and ~738-741), TrustScoreStore::apply_delta() is called in probe paths without a preceding load(). This means decay is not persisted before the delta is applied, so the delta operates on the stale (higher) stored score rather than the true decayed value.

Impact

Slightly more lenient effective trust scores for servers whose scores have decayed since last load(). The error is bounded by the decay accumulated since the last persisting read.

Fix

Ensure load() is called (and decay persisted) before apply_delta() in all probe paths in manager.rs. Consider a wrapper that atomically loads-and-applies.

Priority

P3 — conservative effect (slightly over-lenient scores), no security hole.

Related: #2312 (trust score decay persistence fix)