Add docstrings to public classes (#812)

Add class-level docstrings to five public classes in trustgraph-base:
Flow, LlmService, ConsumerMetrics, ToolClient, and TriplesStoreService.
Each docstring summarises the class's role in the system to aid
discoverability for new contributors.

Signed-off-by: Jenkins, Kenneth Alexander <kjenkins60@gatech.edu>

trustgraph-base/trustgraph/base/flow.py

@@ -2,6 +2,13 @@
 import asyncio
 
 class Flow:
+    """
+    Runtime representation of a deployed flow process.
+    
+    This class maintains internal processor states and orchestrates
+    lifecycles (start, stop) for inputs (consumers) and parameters 
+    that drive data flowing across linked nodes.
+    """
     def __init__(self, id, flow, processor, defn):
 
         self.id = id

trustgraph-base/trustgraph/base/llm_service.py

@@ -42,6 +42,12 @@ class LlmChunk:
     __slots__ = ["text", "in_token", "out_token", "model", "is_final"]
 
 class LlmService(FlowProcessor):
+    """
+    Extensible service processing requests to Large Language Models (LLMs).
+    
+    This class handles the core logic of dispatching text completion or chat requests
+    to integrated underlying LLM providers (e.g. OpenAI, vertex ai).
+    """
 
     def __init__(self, **params):
 

trustgraph-base/trustgraph/base/metrics.py

@@ -3,6 +3,12 @@ from prometheus_client import start_http_server, Info, Enum, Histogram
 from prometheus_client import Counter
 
 class ConsumerMetrics:
+    """
+    Metrics tracking and reporting for flow consumers.
+    
+    This class manages prometheus metrics specifically related to consumers 
+    within the flow, including state, requests, processing time, and queues.
+    """
 
     def __init__(self, processor, flow, name):
 

trustgraph-base/trustgraph/base/tool_client.py

@@ -5,6 +5,13 @@ from . request_response_spec import RequestResponse, RequestResponseSpec
 from .. schema import ToolRequest, ToolResponse
 
 class ToolClient(RequestResponse):
+    """
+    Client for invoking tools over the flow messaging fabric.
+    
+    This class provides an interface to abstract away the messaging mechanics
+    and provides a direct awaitable mechanism for invoking tools and
+    getting their responses.
+    """
 
     async def invoke(self, name, parameters={}, timeout=600):
 

trustgraph-base/trustgraph/base/triples_store_service.py

@@ -15,6 +15,12 @@ logger = logging.getLogger(__name__)
 default_ident = "triples-write"
 
 class TriplesStoreService(FlowProcessor):
+    """
+    Component for maintaining the triples store.
+    
+    This service acts as a processor in the flow that receives knowledge triples 
+    and writes them persistently into an overarching graph database or equivalent backend.
+    """
 
     def __init__(self, **params):