feat: Phase 7A — semantic memory dedup ("sleep cycle" V1)

New table memory_merge_candidates + service functions to cluster
near-duplicate active memories within (project, memory_type) buckets,
draft a unified content via LLM, and merge on human approval. Source
memories become superseded (never deleted); merged memory carries
union of tags, max of confidence, sum of reference_count.

- schema migration for memory_merge_candidates
- atocore.memory.similarity: cosine + transitive clustering
- atocore.memory._dedup_prompt: stdlib-only LLM prompt preserving every specific
- service: merge_memories / create_merge_candidate / get_merge_candidates / reject_merge_candidate
- scripts/memory_dedup.py: host-side detector (HTTP-only, idempotent)
- 5 API endpoints under /admin/memory/merge-candidates* + /admin/memory/dedup-scan
- triage UI: purple "🔗 Merge Candidates" section + "🔗 Scan for duplicates" bar
- batch-extract.sh Step B3 (0.90 daily, 0.85 Sundays)
- deploy/dalidou/dedup-watcher.sh for UI-triggered scans
- 21 new tests (374 → 395)
- docs/PHASE-7-MEMORY-CONSOLIDATION.md covering 7A-7H roadmap

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

deploy/dalidou/batch-extract.sh

@@ -166,6 +166,26 @@ curl -sSf -X POST "$ATOCORE_URL/admin/memory/extend-reinforced" \
     log "WARN: extend-reinforced failed (non-blocking)"
 }
 
+# Step B3: Memory dedup scan (Phase 7A)
+# Nightly at 0.90 (tight — only near-duplicates). Sundays run a deeper
+# pass at 0.85 to catch semantically-similar-but-differently-worded memories.
+if [[ "$(date -u +%u)" == "7" ]]; then
+    DEDUP_THRESHOLD="0.85"
+    DEDUP_BATCH="80"
+    log "Step B3: memory dedup (Sunday deep pass, threshold $DEDUP_THRESHOLD)"
+else
+    DEDUP_THRESHOLD="0.90"
+    DEDUP_BATCH="50"
+    log "Step B3: memory dedup (daily, threshold $DEDUP_THRESHOLD)"
+fi
+python3 "$APP_DIR/scripts/memory_dedup.py" \
+    --base-url "$ATOCORE_URL" \
+    --similarity-threshold "$DEDUP_THRESHOLD" \
+    --max-batch "$DEDUP_BATCH" \
+    2>&1 || {
+    log "WARN: memory dedup failed (non-blocking)"
+}
+
 # Step G: Integrity check (Phase 4 V1)
 log "Step G: integrity check"
 python3 "$APP_DIR/scripts/integrity_check.py" \