feat: add b-route send adapter shell

internal/tools/send_message_broute_adapter.go

@@ -0,0 +1,81 @@
+package tools
+
+import (
+	"context"
+	"fmt"
+	"strings"
+)
+
+type BRouteSendAdapterConfig struct {
+	SidecarPath    string
+	TimeoutSeconds int
+	Mode           string
+}
+
+type bRouteSendMessageConnector struct {
+	config BRouteSendAdapterConfig
+}
+
+func NewBRouteSendMessageConnector(config BRouteSendAdapterConfig) SendMessageConnector {
+	config.Mode = strings.TrimSpace(strings.ToLower(config.Mode))
+	if config.Mode == "" {
+		config.Mode = "disabled"
+	}
+	return bRouteSendMessageConnector{config: config}
+}
+
+func (c bRouteSendMessageConnector) ExecuteSendMessage(_ context.Context, request SendMessageConnectorRequest) (SendMessageConnectorResult, error) {
+	switch c.config.Mode {
+	case "disabled":
+		result := SendMessageConnectorResult{
+			Accepted:      false,
+			Status:        "blocked",
+			ErrorCode:     "broute_mode_blocked",
+			ErrorMessage:  "B-route send adapter is disabled",
+			ConnectorMode: "broute-disabled",
+		}
+		return result, fmt.Errorf(result.ErrorMessage)
+	case "dry_run_contract":
+		if err := validateBRouteSendMessageRequest(request); err != nil {
+			return SendMessageConnectorResult{
+				Accepted:      false,
+				Status:        "failed",
+				ErrorCode:     "broute_invalid_request",
+				ErrorMessage:  err.Error(),
+				ConnectorMode: "broute-dry-run-contract",
+			}, nil
+		}
+		return SendMessageConnectorResult{
+			Accepted:      false,
+			Status:        "blocked",
+			ErrorCode:     "broute_dry_run_only",
+			ErrorMessage:  "B-route adapter dry_run_contract mode validates request shape only and does not start a sidecar",
+			ConnectorMode: "broute-dry-run-contract",
+		}, nil
+	default:
+		result := SendMessageConnectorResult{
+			Accepted:      false,
+			Status:        "blocked",
+			ErrorCode:     "broute_mode_blocked",
+			ErrorMessage:  "B-route send adapter mode is not enabled: " + c.config.Mode,
+			ConnectorMode: "broute-disabled",
+		}
+		return result, fmt.Errorf(result.ErrorMessage)
+	}
+}
+
+func validateBRouteSendMessageRequest(request SendMessageConnectorRequest) error {
+	if strings.TrimSpace(request.TargetRef) == "" {
+		return fmt.Errorf("target_ref is required")
+	}
+	if strings.TrimSpace(request.ContentSHA256) == "" {
+		return fmt.Errorf("content_sha256 is required")
+	}
+	if strings.TrimSpace(request.IdempotencyKeySHA256) == "" {
+		return fmt.Errorf("idempotency_key_sha256 is required")
+	}
+	if request.ExecutionMode != sendMessageProductionMode {
+		return fmt.Errorf("execution_mode must be production")
+	}
+	return nil
+}