feat: briefing conversation management API

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/fabledassistant/services/briefing_conversations.py

@@ -0,0 +1,74 @@
+"""Create and manage briefing conversations."""
+
+import logging
+from datetime import date, datetime, timezone
+
+from sqlalchemy import select
+
+from fabledassistant.models import async_session
+from fabledassistant.models.conversation import Conversation, Message
+
+logger = logging.getLogger(__name__)
+
+
+async def get_or_create_today_conversation(user_id: int, model: str) -> Conversation:
+    """
+    Return today's briefing conversation, creating it if it doesn't exist.
+    """
+    today = date.today()
+    async with async_session() as session:
+        result = await session.execute(
+            select(Conversation).where(
+                Conversation.user_id == user_id,
+                Conversation.conversation_type == "briefing",
+                Conversation.briefing_date == today,
+            )
+        )
+        conv = result.scalars().first()
+        if conv is not None:
+            return conv
+
+        conv = Conversation(
+            user_id=user_id,
+            title=f"Briefing — {today.isoformat()}",
+            model=model,
+            conversation_type="briefing",
+            briefing_date=today,
+        )
+        session.add(conv)
+        await session.commit()
+        await session.refresh(conv)
+        return conv
+
+
+async def post_message(conversation_id: int, role: str, content: str) -> Message:
+    """Append a message to a briefing conversation."""
+    async with async_session() as session:
+        msg = Message(
+            conversation_id=conversation_id,
+            role=role,
+            content=content,
+            status="complete",
+        )
+        session.add(msg)
+        # Bump conversation updated_at
+        conv = await session.get(Conversation, conversation_id)
+        if conv:
+            conv.updated_at = datetime.now(timezone.utc)
+        await session.commit()
+        await session.refresh(msg)
+        return msg
+
+
+async def list_briefing_conversations(user_id: int) -> list[dict]:
+    """Return briefing conversations newest first."""
+    async with async_session() as session:
+        result = await session.execute(
+            select(Conversation).where(
+                Conversation.user_id == user_id,
+                Conversation.conversation_type == "briefing",
+            ).order_by(Conversation.briefing_date.desc().nullslast())
+            .limit(30)
+        )
+        convs = list(result.scalars().all())
+    return [c.to_dict() for c in convs]