회기 연속성과 멀티 케이스 계약을 영속화

apps/api/app/store.py

@@ -104,16 +104,17 @@ class SessionStore:
         state: SessionState,
         persona_id: str | None = None,
         persona_version: int | None = None,
+        case_id: str | None = None,
         session_no: int = 1,
         carry_rapport: float = 0.0,
         goal_stages: list[str] | None = None,
         learner_feedback_enabled: bool = True,
     ) -> InProcSession:
         session_id = uuid4().hex
-        case_id = uuid4().hex
+        stable_case_id = case_id or uuid4().hex
         s = InProcSession(
             session_id=session_id,
-            case_id=case_id,
+            case_id=stable_case_id,
             learner_id=learner_id,
             persona_code=persona.code,
             theory_mode=theory_mode,
@@ -138,6 +139,23 @@ class SessionStore:
     def list(self) -> list[InProcSession]:
         return list(self._sessions.values())
 
+    def find_active(
+        self,
+        *,
+        learner_id: str,
+        persona_id: str | None,
+        persona_code: str,
+    ) -> Optional[InProcSession]:
+        """Return the active session for one learner-persona continuity case."""
+        for session in self._sessions.values():
+            if session.ended or session.learner_id != learner_id:
+                continue
+            if persona_id is not None and session.persona_id == persona_id:
+                return session
+            if session.persona_id is None and session.persona_code == persona_code:
+                return session
+        return None
+
     def append_turn(self, session_id: str, turn: TurnRecord) -> None:
         s = self._sessions.get(session_id)
         if s is not None: