Feat/split data into yaml files, add pagination

[cmcga1125]

Pull Request Summary
🔄 Refactor: YAML-driven content system with multi-language support
Major Changes:

YAML Data Structure: Split questions/answers into separate YAML files (data/questions-en.yaml, questions-zh.yaml, questions-es.yaml)
Single HTML Template: Consolidated separate language HTML files into one dynamic template
Asset Organization: Moved CSS/JS files to /assets/ folder for better structure
Language Selector: Added dropdown in navigation bar for instant language switching
New Features:

✅ Spanish Language Support: Complete translation with 15 questions across 5 categories
✅ Dynamic Content Loading: JavaScript loads content from YAML based on ?lang= parameter
✅ URL-based Language Switching: /pemm-assessment/?lang=es|zh|en
✅ Docker Development Environment: Local setup with nginx mimicking GitHub Pages
Technical Improvements:

Maintainability: Centralized content management in YAML files
Scalability: Easy to add new languages by creating new YAML files
Code Quality: Single source of truth for HTML structure
Developer Experience: Enhanced local development workflow with Docker
Key Files:

assets/style.css - Enhanced with language selector styling
assets/app.js - YAML loading and language detection
index.html - Single dynamic template
INSTRUCTIONS.md - Comprehensive documentation
README-docker.md - Local development guide
Breaking Changes: None - maintains backward compatibility with legacy /zh/ URLs via redirects.

[cmcga1125]

[cmcga1125]

updated to have pagination, for less scrolling

[cmcga1125]

here's a working demo: https://cmcga1125.github.io/pemm-assessment