Use conversation_id as the key in Fin Agent API error examples

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

Author: Magrath

descriptions/0/api.intercom.io.yaml

@@ -28903,7 +28903,7 @@ paths:
                 Conversation not found:
                   value:
                     errors:
-                      external_conversation_id: Conversation not found for the given external_conversation_id
+                      conversation_id: Conversation not found for the given conversation_id
                 No rating requested:
                   value:
                     errors:

descriptions/2.14/api.intercom.io.yaml

@@ -2263,7 +2263,7 @@ paths:
                 Conversation not found:
                   value:
                     errors:
-                      external_conversation_id: Conversation not found for the given external_conversation_id
+                      conversation_id: Conversation not found for the given conversation_id
                 No rating requested:
                   value:
                     errors:

descriptions/2.15/api.intercom.io.yaml

@@ -15060,7 +15060,7 @@ paths:
                 Conversation not found:
                   value:
                     errors:
-                      external_conversation_id: Conversation not found for the given external_conversation_id
+                      conversation_id: Conversation not found for the given conversation_id
                 No rating requested:
                   value:
                     errors:

descriptions/2.16/api.intercom.io.yaml

@@ -4428,7 +4428,7 @@ paths:
                 Conversation not found:
                   value:
                     errors:
-                      external_conversation_id: Conversation not found for the given external_conversation_id
+                      conversation_id: Conversation not found for the given conversation_id
                 No rating requested:
                   value:
                     errors:

descriptions/2.17/api.intercom.io.yaml

@@ -4428,7 +4428,7 @@ paths:
                 Conversation not found:
                   value:
                     errors:
-                      external_conversation_id: Conversation not found for the given external_conversation_id
+                      conversation_id: Conversation not found for the given conversation_id
                 No rating requested:
                   value:
                     errors: