feat(conversations,api,ui): rewind takes the last turns of a thread back, the cut session stays in the store

src/beaver_gateway/conversations/questions.py

@@ -7,7 +7,7 @@ import contextlib
 from typing import TYPE_CHECKING, Any, cast
 from uuid import uuid4
 
-from beaver_gateway.conversations.spawning import Spawning
+from beaver_gateway.conversations.rewinding import Rewinding
 from beaver_gateway.conversations.state import Question
 
 if TYPE_CHECKING:
@@ -16,7 +16,7 @@ if TYPE_CHECKING:
 __all__ = ["Questions"]
 
 
-class Questions(Spawning):
+class Questions(Rewinding):
     async def ask(self, key: str, payload: dict[str, Any]) -> str | None:
         """Show the question and wait; ``None`` when nobody answered in time."""
         conv = await self.get(key)