Fix: Neo4j permissions + stop-on-failure (install.sh)

install.sh

@@ -211,14 +211,13 @@ for epoch in "${EPOCHS[@]}"; do
     # Step 1: Download
     log "  [1/3] Downloading epoch ${epoch}..."
     python scripts/download_epoch_artifacts.py --epoch "$epoch" || {
-        warn "Failed to download epoch ${epoch}, skipping..."
-        continue
+        error "Failed to download epoch ${epoch}. Cannot continue."
     }
 
     # Step 2: Ingest (always pass --merge-neo4j; auto-detect handles empty DB)
     log "  [2/3] Ingesting epoch ${epoch} into databases..."
     python scripts/ingest_epoch.py --epoch "$epoch" --merge-neo4j || {
-        warn "Ingestion failed for epoch ${epoch}"
+        error "Ingestion failed for epoch ${epoch}. Cannot continue."
     }
 
     # Step 3: Delete parquet files to free disk space