feat: add complete sidebar content to match original React CV

Comprehensive update to achieve feature parity with old React implementation.

## Data Layer (Backend)

**Updated Go Models** (internal/models/cv.go):
- Added Course struct (title, institution, location, date, duration, description)
- Added Reference struct (title, URL, type)
- Added Language.Detail field for proficiency descriptions
- Added CV.Courses and CV.References arrays

**Complete Data Population** (data/cv-es.json):
- Added 6 NEW skill categories (42 items):
  * Lenguajes de Programación (11 items: Java, Groovy, PHP, XML, XSLT, ActionScript, Shell, C, C++)
  * Frameworks PHP (4 items: Yii, Zend, WordPress API, Joomla API)
  * Frameworks Java (8 items: Play!, Struts, Spring, Hibernate, Ibatis, Magnolia CMS, XWiki, TESEO)
  * Servidores de Aplicaciones (9 items: Apache, WAMP, MAMP, Tomcat, JBoss, Resin, Jetty, Websphere, Weblogic)
  * CMS y Entornos (6 items: Joomla, WordPress, RapidWeaver, Servoy, WebRatio, Magnolia)
  * Herramientas de Diseño (4 items: Corel, Photoshop, Illustrator, GIMP)

- Updated existing categories with missing items:
  * Ecosistema JavaScript: +Redux, Flux, Gulp, Grunt
  * Desarrollo Web: +JSP, PHP, Handlebars, Moustache, Velocity, Freemarker, jQuery, mooTools, DOM, Ajax, SEO, WebServices
  * Bases de Datos: +Hypersonic, Dominio de SQL
  * Soft Skills: +5 team management items

- Added Catalan language (Comprensión, Level 2)
- Added detail field to all languages (oral/written breakdown)

- Added 4 courses:
  * Servoy World 2011 (Amsterdam, 3 días)
  * Formador de Formadores (FOREM, 150 horas)
  * Windows 2003 Server (Cámara de Comercio, 80 horas)
  * I Jornada Extremeña (Universidad, 3 días)

- Added 8 references:
  * Recommendation letters, portfolios, profiles, CVs

- Fixed driver's license: Tipo C → Tipo B

## Presentation Layer (Frontend)

**Template Updates** (templates/cv-content.html, templates/index.html):
- Skills section: Now renders ALL 13 categories dynamically
- Languages section: Added detail field display
- NEW Courses section: Full course details with institutions
- NEW References section: Clickable links with security attributes
- NEW Other section: Driver's license display
- Responsive grid layout maintained
- Conditional rendering (sections only show if data exists)

**Styling** (static/css/main.css):
- Added .course-item, .course-desc styles
- Added .reference-item, .ref-type styles
- Added .language-detail styles
- Maintained consistent sidebar section styling

## Impact

**Before**: 7 skill categories, 3 languages, 0 courses, 0 references
**After**: 13 skill categories (+6), 4 languages (+1), 4 courses (+4), 8 references (+8)
**Total**: 90+ new data points added

Sidebar now matches original React CV feature-for-feature.

templates/cv-content.html

@@ -13,39 +13,70 @@
 
 <!-- Left Sidebar - Skills -->
 <aside class="cv-sidebar">
-    <!-- Skills Section -->
+    <!-- Skills Section - Dynamically render all categories -->
+    {{range .CV.Skills.Technical}}
     <section class="sidebar-section">
-        <h3 class="sidebar-title">{{if eq .Lang "es"}}Lenguajes de Programación{{else}}Programming Languages{{end}}</h3>
-        {{range .CV.Skills.Technical}}
-        {{if eq .Category "Programming Languages"}}
+        <h3 class="sidebar-title">{{.Category}}</h3>
         <div class="sidebar-content">
             {{range .Items}}<div class="skill-item">{{.}}</div>{{end}}
         </div>
-        {{end}}
-        {{end}}
+    </section>
+    {{end}}
+
+    <!-- Languages Section -->
+    <section class="sidebar-section">
+        <h3 class="sidebar-title">{{if eq .Lang "es"}}Idiomas{{else}}Languages{{end}}</h3>
+        <div class="sidebar-content">
+            {{range .CV.Languages}}
+            <div class="language-item">
+                <strong>{{.Language}}</strong>: {{.Proficiency}}
+                {{if .Detail}}<br><small style="color: #666;">{{.Detail}}</small>{{end}}
+            </div>
+            {{end}}
+        </div>
     </section>
 
+    <!-- Courses Section -->
+    {{if .CV.Courses}}
     <section class="sidebar-section">
-        <h3 class="sidebar-title">{{if eq .Lang "es"}}Desarrollo Web{{else}}Web Development{{end}}</h3>
-        {{range .CV.Skills.Technical}}
-        {{if eq .Category "Web Development"}}
+        <h3 class="sidebar-title">{{if eq .Lang "es"}}Cursos Realizados{{else}}Training Courses{{end}}</h3>
         <div class="sidebar-content">
-            {{range .Items}}<div class="skill-item">{{.}}</div>{{end}}
+            {{range .CV.Courses}}
+            <div class="course-item">
+                <strong>{{.Title}}</strong><br>
+                <small>{{.Institution}} - {{.Location}}</small><br>
+                <small>{{.Date}} ({{.Duration}})</small>
+                {{if .Description}}<p class="course-desc">{{.Description}}</p>{{end}}
+            </div>
+            {{end}}
         </div>
-        {{end}}
-        {{end}}
     </section>
+    {{end}}
 
+    <!-- References Section -->
+    {{if .CV.References}}
     <section class="sidebar-section">
-        <h3 class="sidebar-title">{{if eq .Lang "es"}}Frameworks JavaScript{{else}}Javascript Frameworks{{end}}</h3>
-        {{range .CV.Skills.Technical}}
-        {{if eq .Category "JavaScript Frameworks"}}
+        <h3 class="sidebar-title">{{if eq .Lang "es"}}Referencias{{else}}References{{end}}</h3>
         <div class="sidebar-content">
-            {{range .Items}}<div class="skill-item">{{.}}</div>{{end}}
+            {{range .CV.References}}
+            <div class="reference-item">
+                <a href="{{.URL}}" target="_blank" rel="noopener noreferrer">{{.Title}}</a>
+                <small class="ref-type">({{.Type}})</small>
+            </div>
+            {{end}}
         </div>
-        {{end}}
-        {{end}}
     </section>
+    {{end}}
+
+    <!-- Other Section (Driver's License) -->
+    {{if .CV.Other.DriverLicense}}
+    <section class="sidebar-section">
+        <h3 class="sidebar-title">{{if eq .Lang "es"}}Otros{{else}}Other{{end}}</h3>
+        <div class="sidebar-content">
+            {{if eq .Lang "es"}}Carnet de conducir {{.CV.Other.DriverLicense}}{{else}}Driver's License {{.CV.Other.DriverLicense}}{{end}}
+        </div>
+    </section>
+    {{end}}
 </aside>
 
 <!-- Main Content Area -->
@@ -119,15 +150,4 @@
         {{end}}
     </section>
 
-    <!-- Languages -->
-    <section class="cv-section">
-        <h3 class="section-title">{{if eq .Lang "es"}}Idiomas{{else}}Languages{{end}}</h3>
-        <div class="languages-list">
-            {{range .CV.Languages}}
-            <div class="language-item">
-                <strong>{{.Language}}</strong>: {{.Proficiency}}
-            </div>
-            {{end}}
-        </div>
-    </section>
 </main>