feat: modify reference format (#246)

* feat: modify system prompt, add refuse

* feat: at least return memories

* feat: modify ref

* feat: add memcube retrieval

* fix: test bug

* feat: modify prompt

* feat: modify reference format

Author: CaralHsi

src/memos/mem_os/product.py

@@ -78,7 +78,7 @@ def _format_mem_block(memories_all, max_items: int = 20, max_chars_each: int = 3
         if len(txt) > max_chars_each:
             txt = txt[: max_chars_each - 1] + "…"
         mid = mid or f"mem_{idx}"
-        lines.append(f"{idx}:{mid} :: [{tag}] {txt}")
+        lines.append(f"[{idx}:{mid}] :: [{tag}] {txt}")
     return "\n".join(lines)