Follow up to: https://github.com/zed-industries/zed/pull/31209
Changes default models across multiple providers:
- Zed.dev Default Models in settings: claude-3-7-sonnet-latest →
claude-4-sonnet-latest
- Bedrock Default Model: Claude 3.5 Sonnet v2 → Claude Sonnet 4
- Google AI Default Fast Model: Gemini 1.5 Flash → Gemini 2.0 Flash

Release Notes:

- N/A