fix(memory): mark spawn briefs in the reply log source field

tests/test_recall.py

@@ -5,6 +5,7 @@ from beaver_gateway.conversations.texts import UserSaid
 from beaver_gateway.conversations.envelope import RecallContext
 
 from beaver_agent.hands.calendars import Calendars, Event, Feed
+from beaver_agent.memory.curator import new_replies
 from beaver_agent.memory.recall import (
     LABEL,
     Recall,
@@ -171,8 +172,14 @@ def test_reply_log_appends_one_line_per_message_and_strips_seed(tmp_path: Path)
     assert text.startswith("# реплики Бобра, 2026-09\n")
     assert text.endswith(
         "- 2026-09-01 14:04 · мастер · привет ⏎ ты меня любишь\n"
-        "- 2026-09-01 14:04 · ветка «крипто-карта» · сравни Trustee и RedotPay\n"
+        "- 2026-09-01 14:04 · ветка «крипто-карта» (бриф) · "
+        "сравни Trustee и RedotPay\n"
     )
+    since = datetime(2026, 9, 1, 0, 0, tzinfo=UTC)
+    # пометка брифа не мешает куратору разбирать строку
+    assert new_replies(tmp_path / "реплики", since, "Europe/Warsaw") == [
+        line for line in text.splitlines() if line.startswith("- ")
+    ]
     assert date.fromisoformat("2026-09-01")  # tz shift stays inside the month here