Feature/rag parameters (#311)

* Change document-rag and graph-rag processing so that the user can
specify parameters.  Changes in Pulsar services, Pulsar message
schemas, gateway and command-line tools.  User-visible changes in
new parameters on command-line tools.

* Fix bugs, graph-rag working

* Get subgraph truncation in the right place

* Graph RAG and document RAG working and configurable

* Multi-hop path traversal GraphRAG

* Add safety valve for path_size set too high

trustgraph-flow/trustgraph/gateway/document_rag.py

@@ -23,6 +23,7 @@ class DocumentRagRequestor(ServiceRequestor):
             query=body["query"],
             user=body.get("user", "trustgraph"),
             collection=body.get("collection", "default"),
+            doc_limit=int(body.get("doc-limit", 20)),
         )
 
     def from_response(self, message):

trustgraph-flow/trustgraph/gateway/graph_rag.py

@@ -23,6 +23,10 @@ class GraphRagRequestor(ServiceRequestor):
             query=body["query"],
             user=body.get("user", "trustgraph"),
             collection=body.get("collection", "default"),
+            entity_limit=int(body.get("entity-limit", 50)),
+            triple_limit=int(body.get("triple-limit", 30)),
+            max_subgraph_size=int(body.get("max-subgraph-size", 1000)),
+            max_path_length=int(body.get("max-path-length", 2)),
         )
 
     def from_response(self, message):