feat(agent): route chat through selected model

src/lib/llm/index.ts

@@ -13,8 +13,8 @@ export type {
 export { getLlmConfig, isLlmConfigured } from "./config";
 export { createMockLlmClient } from "./mock";
 
-export function createLlmClient(override?: LlmClient): LlmClient {
-  if (override) return override;
+export function createLlmClient(options?: { model?: string; override?: LlmClient }): LlmClient {
+  if (options?.override) return options.override;
 
   const config = getLlmConfig();
   if (config.provider === "mock" || !config.baseUrl) {
@@ -24,6 +24,6 @@ export function createLlmClient(override?: LlmClient): LlmClient {
   return createOpenAiCompatibleClient({
     baseUrl: config.baseUrl,
     apiKey: config.apiKey,
-    model: config.model,
+    model: options?.model ?? config.model,
   });
 }