feat: enhance CV with project title links, experience durations, certifications, and improved navigation

## Project Title Links
- Add projectName and projectDesc fields to Project struct
- Split project titles to make only project name clickable
- Update template logic for conditional title rendering
- Apply changes to both English and Spanish versions

## Experience Duration Display
- Restore duration calculation display in experience section
- Move duration from date line to after company name
- Style duration in light gray (#999) for subtle appearance
- Calculate durations dynamically (e.g., "4 years 10 months")

## Certifications Section Enhancement
- Add Codecademy Certifications (2022-2024) with AI Transformers and React courses
- Add LinkedIn Learning Certifications (2019-2020) with 5 professional courses
- Implement colored icon system with brand colors (purple, cyan, green, etc.)
- Use responsibilities format matching Third Party Contributions layout
- Reorder courses chronologically (most recent first)

## localStorage Improvements
- Save CV length preference (short/long)
- Save logos visibility preference (show/hide)
- Save theme preference (default/clean)
- Restore all preferences on page load

## Navigation UX Enhancements
- Fix scroll positioning to show sections below action bar
- Add keepHeaderVisible flag to maintain header visibility after navigation
- Ensure smooth scrolling with proper offset calculations
- Reset flag on scroll up to restore normal hide/show behavior

## Files Modified
- internal/models/cv.go: Add ProjectName, ProjectDesc fields
- templates/cv-content.html: Update project and experience rendering
- static/css/main.css: Add duration-text styling
- templates/index.html: Enhance scroll behavior and localStorage
- data/cv-*.json: Add certifications, split project titles, reorder courses
- static/images/courses/: Add codecademy.png, linkedin.png

data/cv-en.json

@@ -664,6 +664,35 @@
     }
   ],
   "courses": [
+    {
+      "title": "Codecademy Certifications",
+      "institution": "Codecademy",
+      "courseLogo": "codecademy.png",
+      "location": "Online",
+      "date": "2022-2024",
+      "duration": "Various",
+      "shortDescription": "Professional development courses in AI and modern web technologies through Codecademy's interactive learning platform.",
+      "responsibilities": [
+        "<iconify-icon icon='mdi:robot' width='60' height='60' class='default-company-icon' style='color: #9333EA;'></iconify-icon><div><strong>Intro to AI Transformers Course</strong> <em>April 2024</em>: Comprehensive introduction to transformer architecture and AI models, covering attention mechanisms, encoder-decoder structures, and practical applications in natural language processing</div>",
+        "<iconify-icon icon='mdi:react' width='60' height='60' class='default-company-icon' style='color: #61DAFB;'></iconify-icon><div><strong>Learn React Course</strong> <em>March 2022</em>: Complete React framework training covering components, state management, hooks, lifecycle methods, and modern React development practices</div>"
+      ]
+    },
+    {
+      "title": "LinkedIn Learning Certifications",
+      "institution": "LinkedIn Learning",
+      "courseLogo": "linkedin.png",
+      "location": "Online",
+      "date": "2019-2020",
+      "duration": "Various",
+      "shortDescription": "Professional development courses in SAP technologies, UX design, security, and data analytics through LinkedIn Learning's comprehensive training platform.",
+      "responsibilities": [
+        "<iconify-icon icon='mdi:book-open-page-variant' width='60' height='60' class='default-company-icon' style='color: #D97706;'></iconify-icon><div><strong>Aprende lectura rápida</strong> <em>April 2020</em>: Speed reading techniques and comprehension strategies for professional development and efficient information processing</div>",
+        "<iconify-icon icon='mdi:cloud' width='60' height='60' class='default-company-icon' style='color: #0FAAFF;'></iconify-icon><div><strong>A Tour of the SAP Cloud Platform</strong> <em>February 2020</em>: Comprehensive overview of SAP Cloud Platform services, architecture, and integration capabilities for enterprise cloud solutions</div>",
+        "<iconify-icon icon='mdi:android' width='60' height='60' class='default-company-icon' style='color: #3DDC84;'></iconify-icon><div><strong>Learning Android Security</strong> <em>February 2020</em>: Android security best practices, encryption methods, secure coding practices, and mobile application security fundamentals</div>",
+        "<iconify-icon icon='mdi:account-group' width='60' height='60' class='default-company-icon' style='color: #EC4899;'></iconify-icon><div><strong>Persuasive UX: Creating Credibility</strong> <em>January 2020</em>: User experience design principles focused on building trust, credibility, and persuasive design patterns for web applications</div>",
+        "<iconify-icon icon='mdi:database' width='60' height='60' class='default-company-icon' style='color: #3B82F6;'></iconify-icon><div><strong>Big Data Foundations: Techniques and Concepts</strong> <em>December 2019</em>: Fundamentals of big data technologies, distributed computing, data processing frameworks, and analytics techniques</div>"
+      ]
+    },
     {
       "title": "Servoy World 2011",
       "institution": "Servoy",
@@ -738,6 +767,8 @@
   "projects": [
     {
       "title": "Somos Una Ola - Beach Cleaning Initiative",
+      "projectName": "Somos Una Ola",
+      "projectDesc": "Beach Cleaning Initiative",
       "url": "https://somosunaola.org",
       "projectLogo": "somosunaola.png",
       "location": "La Palma, Canary Islands",
@@ -753,6 +784,8 @@
     },
     {
       "title": "Herrumbre Vivo Arte - Artist Portfolio Website",
+      "projectName": "Herrumbre Vivo Arte",
+      "projectDesc": "Artist Portfolio Website",
       "url": "https://herrumbrevivoarte.com",
       "projectLogo": "herrumbre-vivo.png",
       "location": "Fuencaliente, La Palma",
@@ -768,6 +801,8 @@
     },
     {
       "title": "La Porra.club - Football Prediction Platform",
+      "projectName": "La Porra.club",
+      "projectDesc": "Football Prediction Platform",
       "url": "https://laporra.club",
       "projectLogo": "laporra.png",
       "gitRepoUrl": "/Users/txeo/laporra",
@@ -784,6 +819,8 @@
     },
     {
       "title": "CDC Starter Kit - SAP Customer Data Cloud Demo",
+      "projectName": "CDC Starter Kit",
+      "projectDesc": "SAP Customer Data Cloud Demo",
       "url": "https://gigyademo.com/cdc-starter-kit/",
       "projectLogo": "sap.png",
       "location": "Online",