7615dedf9e
NREM in the reframe is replay-and-consolidation of recent encoded content. Excluding previously_retrieved sources turns NREM into novelty-finding, which is Late REM's job. NREM should re-traverse already-encoded content; that's what consolidation is. The May 2 abort surfaced this — 52 sources accumulated in the exclusion list, all of them in NREM's similarity band for the recurring research/fabrication/teaching query. The dreamer hit zero retrievable chunks not because the corpus was empty, but because everything semantically aligned was excluded. Late REM and Early REM keep the exclusion mechanism — novelty is their job. Session-scoped exclusion (nrem_high_sources flowing into Early REM) also preserved. The 500/400 trim on retrieved_sources is preserved for the remaining stages that still use it.