Add hybrid text plus vector memory search

.env.example

@@ -19,6 +19,13 @@ OPENBRAIN__DATABASE__POOL_SIZE=10
 OPENBRAIN__EMBEDDING__MODEL_PATH=models/all-MiniLM-L6-v2
 OPENBRAIN__EMBEDDING__DIMENSION=384
 
+# Hybrid query scoring
+OPENBRAIN__QUERY__VECTOR_WEIGHT=0.6
+OPENBRAIN__QUERY__TEXT_WEIGHT=0.4
+# Backward-compatible plain env aliases
+# VECTOR_WEIGHT=0.6
+# TEXT_WEIGHT=0.4
+
 # Authentication (optional)
 OPENBRAIN__AUTH__ENABLED=false
 # Comma-separated list of API keys