Update universal-2 description in speech model selection page

[devin-ai-integration]

Summary

Updates the Universal-2 model description in the speech model selection table from "Our fastest model with the broadest language coverage." to "Our highly accurate, fastest performing model with support across 99 languages."

The change is applied consistently across all three tabs (Python SDK, JavaScript SDK, and API) in the model selection table.

Review & Testing Checklist for Human

• Verify the new description wording matches the intended copy
• Check that the docs page renders correctly with the updated text

Notes

Requested by @brit9612

Link to Devin run: https://app.devin.ai/sessions/69f50268e39d482ba16604a66376918b

[devin-ai-integration]

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