[verified] fix: preserve timestamps in chat history

tests/test_pheby.py

@@ -432,6 +432,32 @@ class TestAttachments:
 # Tool events / approvals / clarifications / cancellation (bridge)
 # ═══════════════════════════════════════════════════════════════════════════
 class TestBridge:
+    @pytest.mark.asyncio
+    async def test_history_converts_numeric_hermes_timestamps_to_iso(self, monkeypatch):
+        from pheby import hermes_bridge as hb
+
+        class Store:
+            def peek_session_id(self, _key):
+                return "session-1"
+
+        class DB:
+            def get_messages_as_conversation(self, _session_id, include_row_ids=False):
+                assert include_row_ids is True
+                return [
+                    {"_row_id": 10, "role": "user", "content": "hello", "timestamp": 1_789_000_000.25},
+                    {"_row_id": 11, "role": "assistant", "content": "reply", "timestamp": 1_789_000_001.5},
+                ]
+
+        monkeypatch.setattr(hb, "_session_store", lambda: Store())
+        monkeypatch.setattr(hb, "_session_db", lambda: DB())
+
+        history, found = await hb.conversation_history("conv", 20)
+
+        assert found is True
+        assert [message["message_id"] for message in history] == ["m10", "m11"]
+        assert history[0]["ts"] == "2026-09-10T00:26:40.250000+00:00"
+        assert history[1]["ts"] == "2026-09-10T00:26:41.500000+00:00"
+
     @pytest.mark.asyncio
     async def test_tool_start_event_is_structured_not_text(self, tmp_path,
                                                             monkeypatch):