feat: add company names with optional clickable links to experience section

- Add companyURL field to Experience model (optional)
- Update cv-content.html template to display company name with conditional link
- Add company-link CSS styling for clickable company names
- Add companyURL data for major companies (Olympic Broadcasting, AENA, SAP, Gigya, Everis, Indra)
- Companies without URLs display as plain text, maintaining flexibility

This addresses the issue where company names were missing from the experience section
and ensures links are included throughout the CV as per the original React version.

internal/models/cv.go

@@ -43,6 +43,7 @@ type Personal struct {
 type Experience struct {
 	Position         string   `json:"position"`
 	Company          string   `json:"company"`
+	CompanyURL       string   `json:"companyURL,omitempty"` // Optional URL for company website
 	CompanyLogo      string   `json:"companyLogo"`
 	Location         string   `json:"location"`
 	StartDate        string   `json:"startDate"`