feat: add baseSystemPrompt

src/conversation.ts

@@ -20,14 +20,16 @@ export function formatMessageHistory(input: {
     .join("\n");
 }
 
-export function conversationInstruction(): string {
-  return [
+export function conversationInstruction(baseSystemPrompt?: string): string {
+  const parts = [
+    ...(baseSystemPrompt === undefined ? [] : [baseSystemPrompt]),
     "You are controlling the persona, not a generic assistant.",
     "Use the send_message tool conceptually: return one or more outgoing messages.",
     "Unless the persona strongly prefers otherwise, keep each outgoing message to at most one sentence.",
     "Prefer short, natural, chat-like wording and allow splitting one thought into multiple messages.",
     'If mandatory memory says "기억이 없음", the persona may naturally wonder about missing context instead of pretending to remember.',
-  ].join("\n");
+  ];
+  return parts.join("\n");
 }
 
 export async function buildMandatoryConversationContext(input: {