feat(ai): add Together AI provider

packages/coding-agent/src/cli/args.ts

@@ -314,6 +314,7 @@ ${chalk.bold("Environment Variables:")}
   CEREBRAS_API_KEY                 - Cerebras API key
   XAI_API_KEY                      - xAI Grok API key
   FIREWORKS_API_KEY                - Fireworks API key
+  TOGETHER_API_KEY                 - Together AI API key
   OPENROUTER_API_KEY               - OpenRouter API key
   AI_GATEWAY_API_KEY               - Vercel AI Gateway API key
   ZAI_API_KEY                      - ZAI API key

packages/coding-agent/src/core/model-registry.ts

@@ -105,6 +105,7 @@ const OpenAICompletionsCompatSchema = Type.Object({
 		Type.Union([
 			Type.Literal("openai"),
 			Type.Literal("openrouter"),
+			Type.Literal("together"),
 			Type.Literal("deepseek"),
 			Type.Literal("zai"),
 			Type.Literal("qwen"),

packages/coding-agent/src/core/model-resolver.ts

@@ -34,6 +34,7 @@ export const defaultModelPerProvider: Record<KnownProvider, string> = {
 	"moonshotai-cn": "kimi-k2.6",
 	huggingface: "moonshotai/Kimi-K2.6",
 	fireworks: "accounts/fireworks/models/kimi-k2p6",
+	together: "moonshotai/Kimi-K2.6",
 	opencode: "kimi-k2.6",
 	"opencode-go": "kimi-k2.6",
 	"kimi-coding": "kimi-for-coding",

packages/coding-agent/src/core/provider-display-names.ts

@@ -21,6 +21,7 @@ export const BUILT_IN_PROVIDER_DISPLAY_NAMES: Record<string, string> = {
 	"opencode-go": "OpenCode Go",
 	openai: "OpenAI",
 	openrouter: "OpenRouter",
+	together: "Together AI",
 	"vercel-ai-gateway": "Vercel AI Gateway",
 	xai: "xAI",
 	zai: "ZAI",