degradedLookups

Calls that ran uncached because the Embedder threw and EmbedFailurePolicy.FALL_BACK_TO_COMPUTE stepped aside.

Counted per call, not per prompt: one degraded SemanticCache.getOrPutAll of fifty prompts is 1. These are not in lookups — no lookup happened — so a rising number here alongside a flat lookups is the cache quietly turning into a pass-through, which is otherwise the one failure mode with no signal attached to it. Stays 0 under EmbedFailurePolicy.PROPAGATE, where the caller sees the exception instead.