Update docs for 2.2 release

- Update protocol specs
- Update protocol docs
- Update API specs

specs/api/components/schemas/agent/AgentResponse.yaml

@@ -10,6 +10,7 @@ properties:
       - observation
       - answer
       - final-answer
+      - explain
       - error
     example: answer
   content:
@@ -29,6 +30,11 @@ properties:
     type: string
     description: Named graph containing the explainability data
     example: urn:graph:retrieval
+  explain_triples:
+    type: array
+    description: Provenance triples for this explain event (inline, no follow-up query needed)
+    items:
+      $ref: '../common/Triple.yaml'
   end-of-message:
     type: boolean
     description: Current chunk type is complete (streaming mode)

specs/api/components/schemas/rag/DocumentRagResponse.yaml

@@ -18,6 +18,11 @@ properties:
     type: string
     description: Named graph containing the explainability data
     example: urn:graph:retrieval
+  explain_triples:
+    type: array
+    description: Provenance triples for this explain event (inline, no follow-up query needed)
+    items:
+      $ref: '../common/Triple.yaml'
   end-of-stream:
     type: boolean
     description: Indicates LLM response stream is complete

specs/api/components/schemas/rag/GraphRagResponse.yaml

@@ -18,6 +18,11 @@ properties:
     type: string
     description: Named graph containing the explainability data
     example: urn:graph:retrieval
+  explain_triples:
+    type: array
+    description: Provenance triples for this explain event (inline, no follow-up query needed)
+    items:
+      $ref: '../common/Triple.yaml'
   end_of_stream:
     type: boolean
     description: Indicates LLM response stream is complete