Add Speech AI plugin to Integrations

[fasuizu-br]

Summary

Adds Speech AI plugin to the Integrations section.

Speech AI is a Claude plugin providing:

• Pronunciation assessment with phoneme-level scoring (17MB model, <300ms latency)
• Text-to-speech synthesis
• Speech-to-text transcription
• 8 MCP tools for language learning, accessibility, and voice applications

This enables Claude users to add speech and pronunciation capabilities to their workflows.

Checklist

• Entry added to existing Integrations section
• Description follows the existing format
• Link points to a public GitHub repository