The MCP tool context_feedback should record whether a retrieved CXU was helpful or unhelpful so that the feedback can feed Q-values.

`context_feedback`

— PYRANA_Internal_Knowledge_Graph_Specification.md

Report that a retrieved CXU was helpful/unhelpful

— PYRANA_Internal_Knowledge_Graph_Specification.md

(feeds Q-values)

— PYRANA_Internal_Knowledge_Graph_Specification.md