Fix mock content fallback to preserve original HTML content

- Remove [Mock: id] placeholder text generation
- Return nil for missing content to preserve original HTML
- Maintain data attributes for editor functionality
- Clean development experience with realistic content mixing

insertr-cli/pkg/content/mock.go

@@ -1,7 +1,6 @@
 package content
 
 import (
-	"fmt"
 	"time"
 )
 
@@ -104,16 +103,8 @@ func (m *MockClient) GetContent(siteID, contentID string) (*ContentItem, error)
 		return &item, nil
 	}
 
-	// Return fallback content for missing items during development
-	fallback := &ContentItem{
-		ID:        contentID,
-		SiteID:    siteID,
-		Value:     fmt.Sprintf("[Mock: %s]", contentID),
-		Type:      "text",
-		UpdatedAt: time.Now().Format(time.RFC3339),
-	}
-
-	return fallback, nil
+	// Return nil for missing content - this will preserve original HTML content
+	return nil, nil
 }
 
 // GetBulkContent fetches multiple content items by IDs