feat: add course logo support with servoy, forem, and camaracomercio logos

- Add courseLogo field to Course struct in Go
- Update template to display course logos with fallback to school icon
- Add CSS styling for course logo images (80x80px, contained, bordered)
- Add logos to three courses in both English and Spanish:
  * Servoy World 2011 (servoy.png)
  * Train the Trainers / Formador de Formadores (forem.png)
  * Windows 2003 Server (camaracomercio.png)
- Course logos stored in /static/images/courses/ folder
- Similar implementation to project logos with error handling

internal/models/cv.go

@@ -137,6 +137,7 @@ type Certification struct {
 type Course struct {
 	Title            string   `json:"title"`
 	Institution      string   `json:"institution"`
+	CourseLogo       string   `json:"courseLogo,omitempty"` // Optional logo filename
 	Location         string   `json:"location"`
 	Date             string   `json:"date"`
 	Duration         string   `json:"duration"`