feat: Implement IPA (International Phonetic Alphabet) translation support

[konard]

Summary

This PR implements comprehensive IPA (International Phonetic Alphabet) translation support for the Human Language project, resolving issue #1. The implementation enables universal pronunciation representation that bridges all human languages.

Key Features Implemented

✅ IPA Transcription Retrieval

• Integration with Wikidata P898 property for IPA transcriptions
• Support for multiple pronunciations per entity
• Automatic retrieval and caching of pronunciation data

✅ Multi-Language Pronunciation Support

• Language qualifier support (P407) for pronunciation variants
• Pronunciation variety qualifier support (P5237) for regional dialects
• Proper handling of different language-specific pronunciations

✅ Beautiful UI Display

• Visual IPA display with /phonemic/ notation
• Seamless integration into entity viewer
• Language and dialect information display
• Responsive design matching existing UI theme

✅ Robust Architecture

• Extended both Node.js and browser API clients
• Comprehensive error handling
• Full caching integration for performance
• Type-safe implementation with proper data validation

✅ Comprehensive Testing

• Test suite with real Wikidata entities (Q102090 "Apache")
• Edge case handling verification
• Both successful and error path testing
• Automated test results logging

Technical Implementation

API Extensions

• getIpaTranscription() method added to WikidataAPIClient
• Support for P898, P407, and P5237 Wikidata properties
• Consistent interface across Node.js and browser environments

UI Integration

• IPA display section in entity viewer (entities.html)
• Conditional rendering when pronunciation data available
• Visual consistency with existing design system
• Proper language label resolution

Test Coverage

• Created examples/ipa-test.mjs with comprehensive test cases
• Successfully validated with Apache entity (Q102090) showing multiple language pronunciations
• Verified error handling for non-existent entities

Documentation Updates

Updated README.md to reflect completed IPA functionality:

• Moved IPA support from roadmap to implemented features
• Added new "IPA Support" section to key features
• Updated architecture documentation
• Marked Phase 2 milestone as partially complete

Test Results

📝 Testing entity: Q102090 (Apache)
✅ Found 2 IPA transcription(s):
   1. /əˈpætʃiː/ (Language: Q1860 - English)
   2. /a.paʃ/ (Language: Q150 - French)

Impact

This implementation fulfills the vision of creating "single human meta language that will be able to unify all languages" by providing:

• Universal phonetic representation across all languages
• Foundation for true cross-linguistic understanding
• Semantic precision in pronunciation data
• Integration with the world's largest knowledge base

The feature enables users to see how words are pronounced in different languages and dialects, supporting the project's goal of language unification through semantic understanding.

🤖 Generated with Claude Code

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Resolves #1