feat(realtime): complete fake channel reply flow

backend/internal/handler/api/v1/conversation_handler.go

@@ -4,12 +4,14 @@ import (
 	"context"
 	"errors"
 	"io"
+	"net"
 	"net/http"
 	"strconv"
 	"strings"
 
 	"github.com/gin-gonic/gin"
 
+	"github.com/gochat/gochat/internal/llm"
 	"github.com/gochat/gochat/internal/model"
 	"github.com/gochat/gochat/internal/service"
 	"github.com/gochat/gochat/pkg/pagination"
@@ -1055,6 +1057,29 @@ func handleServiceError(c *gin.Context, err error) {
 		return
 	}
 	errMsg := err.Error()
+	if errors.Is(err, llm.ErrProviderNotConfigured) {
+		response.AbortWithStatusError(c, http.StatusServiceUnavailable, response.ErrCopilotNotConfigured, errMsg)
+		return
+	}
+	var providerErr *llm.APIError
+	if errors.As(err, &providerErr) {
+		switch providerErr.StatusCode {
+		case http.StatusUnauthorized, http.StatusForbidden:
+			response.AbortWithStatusError(c, http.StatusBadGateway, response.ErrCopilotProviderAuth, "Copilot provider authentication failed")
+		case http.StatusNotFound:
+			response.AbortWithStatusError(c, http.StatusBadGateway, response.ErrCopilotModelNotFound, "Copilot provider endpoint or model was not found")
+		case http.StatusTooManyRequests:
+			response.AbortWithStatusError(c, http.StatusTooManyRequests, response.ErrCopilotProviderRateLimited, "Copilot provider rate limit exceeded")
+		default:
+			response.AbortWithStatusError(c, http.StatusBadGateway, response.ErrCopilotProviderUnreachable, "Copilot provider request failed")
+		}
+		return
+	}
+	var networkErr net.Error
+	if errors.Is(err, context.DeadlineExceeded) || (errors.As(err, &networkErr) && networkErr.Timeout()) {
+		response.AbortWithStatusError(c, http.StatusGatewayTimeout, response.ErrCopilotProviderTimeout, "Copilot provider request timed out")
+		return
+	}
 	lower := strings.ToLower(errMsg)
 	if strings.Contains(lower, "not found") || strings.Contains(lower, "record not found") {
 		response.AbortWithStatusError(c, http.StatusNotFound, response.ErrNotFound, errMsg)

backend/internal/handler/api/v1/conversation_serializer.go

@@ -694,6 +694,7 @@ func serializeContactWithContext(ctx context.Context, contact *model.Contact) ma
 		"custom_attributes":     jsonObject(contact.CustomAttributes),
 		"last_activity_at":      int64Value(contact.LastActivityAt),
 		"created_at":            contact.CreatedAt.Unix(),
+		"type":                  "contact",
 	}
 }
 
@@ -710,6 +711,7 @@ func serializeUser(user *model.User, accountID uint) map[string]any {
 		"name":                user.Name,
 		"role":                nonEmpty(user.Role, "agent"),
 		"thumbnail":           user.AvatarURL,
+		"type":                "user",
 	}
 	if attrs := jsonObject(user.CustomAttributes); len(attrs) > 0 {
 		payload["custom_attributes"] = attrs

backend/internal/handler/api/v1/conversation_serializer_test.go

@@ -390,9 +390,19 @@ func TestSerializeContactUsesPresenceStatus(t *testing.T) {
 	payload := serializeContactWithContext(ctx, contact)
 
 	require.Equal(t, "online", payload["availability_status"])
+	require.Equal(t, "contact", payload["type"])
 	require.Equal(t, "offline", serializeContact(contact)["availability_status"])
 }
 
+func TestSerializeUserIncludesSenderType(t *testing.T) {
+	user := &model.User{AccountID: 7, Name: "Support Agent"}
+	user.ID = 43
+
+	payload := serializeUser(user, user.AccountID)
+
+	require.Equal(t, "user", payload["type"])
+}
+
 func TestSerializeCRMContactUsesPresenceStatus(t *testing.T) {
 	contact := &model.Contact{AccountID: 9, Name: "CRM Online Contact"}
 	contact.ID = 99