ci: remove unused canvasUserMessage type to fix lint on staging

internal/handlers/a2a_proxy_helpers.go:412 had an unused struct that
causes golangci-lint `unused` failure on every PR targeting staging.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

workspace-server/internal/handlers/a2a_proxy_helpers.go

@@ -407,15 +407,6 @@ func validateCallerToken(ctx context.Context, c *gin.Context, callerID string) e
 // matching (the wsauth errors are typed for the invalid case).
 var errInvalidCallerToken = errors.New("missing caller auth token")
 
-// canvasUserMessage holds the extracted user message extracted from an
-// A2A canvas request body for broadcasting to other sessions.
-type canvasUserMessage struct {
-	Message   string                               `json:"message,omitempty"`
-	Parts     []map[string]interface{}              `json:"parts,omitempty"`
-	MessageID string                               `json:"messageId,omitempty"`
-	Attachments []map[string]interface{}            `json:"attachments,omitempty"`
-}
-
 // extractCanvasUserMessage parses an A2A JSON-RPC request body and extracts
 // the user-authored text and attachments from a canvas-initiated message/send.
 // Returns nil when the body is not a canvas user message (empty, malformed,

workspace-server/internal/handlers/restart_context.go

@@ -139,6 +139,9 @@ func loadRestartContextData(ctx context.Context, workspaceID string) restartCont
 				keySet[k] = struct{}{}
 			}
 		}
+		if err := rows.Err(); err != nil {
+			log.Printf("restart-context: global_secrets rows error: %v", err)
+		}
 		rows.Close()
 	}
 	if rows, err := db.DB.QueryContext(ctx,
@@ -150,6 +153,9 @@ func loadRestartContextData(ctx context.Context, workspaceID string) restartCont
 				keySet[k] = struct{}{}
 			}
 		}
+		if err := rows.Err(); err != nil {
+			log.Printf("restart-context: workspace_secrets rows error: %v", err)
+		}
 		rows.Close()
 	}
 	for k := range keySet {