Add MiniMax provider support (#656 by @dannote)

- Add minimax to KnownProvider and Api types
- Add MINIMAX_API_KEY to getEnvApiKey()
- Generate MiniMax-M2 and MiniMax-M2.1 models
- Add context overflow detection pattern
- Add tests to all required test files
- Update README and CHANGELOG with attribution

Also fixes:
- Bedrock duplicate toolResult ID when content has multiple blocks
- Sandbox extension unused parameter lint warning

packages/ai/src/stream.ts

@@ -98,6 +98,7 @@ export function getEnvApiKey(provider: any): string | undefined {
 		openrouter: "OPENROUTER_API_KEY",
 		zai: "ZAI_API_KEY",
 		mistral: "MISTRAL_API_KEY",
+		minimax: "MINIMAX_API_KEY",
 		opencode: "OPENCODE_API_KEY",
 	};