fix: cloudflare-ai-gateway sdk.chat undefined error (#6407)

packages/opencode/src/provider/provider.ts

@@ -374,7 +374,7 @@ export namespace Provider {
       return {
         autoload: true,
         async getModel(sdk: any, modelID: string, _options?: Record<string, any>) {
-          return sdk.chat(modelID)
+          return sdk.languageModel(modelID)
         },
         options: {
           baseURL: `https://gateway.ai.cloudflare.com/v1/${accountId}/${gateway}/compat`,