perf(session-search): project fields before enrichment

tests/tools/test_session_search.py

@@ -113,6 +113,29 @@ class TestBrowseShape:
 # =========================================================================
 
 class TestDiscoveryShape:
+    def test_discovery_field_plan_preserves_full_default_result(self, db, monkeypatch):
+        _seed_modpack_sessions(db)
+        original = db.search_messages
+        requested_fields = None
+
+        def search_spy(*args, **kwargs):
+            nonlocal requested_fields
+            requested_fields = kwargs.get("fields")
+            return original(*args, **kwargs)
+
+        monkeypatch.setattr(db, "search_messages", search_spy)
+
+        result = json.loads(session_search(query="modpack", limit=1, db=db))
+
+        assert result["success"] is True
+        assert requested_fields is not None
+        assert "context" not in requested_fields
+        assert len(result["results"]) == 1
+        hit = result["results"][0]
+        assert "bookend_start" in hit
+        assert hit["messages"]
+        assert "bookend_end" in hit
+
     def test_discovery_result_has_bookends_and_window(self, db):
         _seed_modpack_sessions(db)
         result = json.loads(session_search(query="modpack", limit=3, db=db))