Adjust concurrency limits more LLM friendly settings for new comers

- Lowered max async LLM processes to 4
- Enabled LLM cache for entity extraction
- Reduced max parallel insert to 2

env.example

@@ -50,7 +50,8 @@
 # MAX_TOKEN_SUMMARY=500        # Max tokens for entity or relations summary
 # SUMMARY_LANGUAGE=English
 # MAX_EMBED_TOKENS=8192
-# ENABLE_LLM_CACHE_FOR_EXTRACT=false  # Enable LLM cache for entity extraction, defaults to false
+# ENABLE_LLM_CACHE_FOR_EXTRACT=true  # Enable LLM cache for entity extraction
+# MAX_PARALLEL_INSERT=2        # Maximum number of parallel processing documents in pipeline
 
 ### LLM Configuration (Use valid host. For local services installed with docker, you can use host.docker.internal)
 LLM_BINDING=ollama