Restore active sessions on startup

app/memory/repository.py

@@ -3,7 +3,7 @@
 import logging
 import uuid
 from datetime import datetime
-from sqlalchemy import select, update
+from sqlalchemy import func, select, update
 from sqlalchemy.ext.asyncio import AsyncSession
 
 from app.memory.models import (
@@ -56,6 +56,16 @@ class Repository:
         result = await self.session.execute(stmt)
         return result.scalars().first()
 
+    async def get_active_sessions(self) -> list[StreamSession]:
+        """Retrieve sessions that are still marked active."""
+        stmt = (
+            select(StreamSession)
+            .where(StreamSession.is_active.is_(True))
+            .order_by(StreamSession.started_at.asc())
+        )
+        result = await self.session.execute(stmt)
+        return list(result.scalars().all())
+
     # Chat Message operations
 
     async def add_chat_message(
@@ -95,6 +105,14 @@ class Repository:
         result = await self.session.execute(stmt)
         return list(result.scalars().all())
 
+    async def count_messages(self, session_id: str) -> int:
+        """Count chat messages stored for a session."""
+        stmt = select(func.count()).select_from(ChatMessage).where(
+            ChatMessage.session_id == session_id
+        )
+        result = await self.session.execute(stmt)
+        return result.scalar_one()
+
     async def get_messages_since(
         self, session_id: str, since: datetime
     ) -> list[ChatMessage]: