feat(article-discuss): unify /news + briefing entry points, persist summaries to RAG

Both the /news discuss button and the briefing discuss button now call a
shared seed_article_discussion() helper that stages the synthetic
read_article tool exchange and the conversational seed prompt — behavior
stays byte-identical across entry points. /news also auto-starts
generation so the chat screen lands on an in-flight stream.

First assistant reply in a seeded article conversation is persisted as a
Note (tags: article-summary + article topics) and backlinked via
rss_items.discussion_note_id, so the knowledge base stops being amnesiac
about articles the user has engaged with.

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

src/fabledassistant/routes/chat.py

@@ -510,47 +510,66 @@ async def delete_model_route():
 @chat_bp.route("/from-article/<int:item_id>", methods=["POST"])
 @login_required
 async def create_conversation_from_article(item_id: int):
-    """Create a chat conversation seeded with an RSS article's content."""
+    """Create a chat conversation seeded for article discussion and auto-run.
+
+    Mirrors the briefing ``discuss_article`` route: creates a fresh
+    conversation, stages the shared synthetic read_article exchange + seed
+    prompt, then kicks off generation so the client lands on an in-flight
+    stream. The Flutter and web chat screens reconnect to the running buffer
+    on mount.
+    """
     from sqlalchemy import select as _select
     from fabledassistant.models import async_session as _async_session
-    from fabledassistant.models.conversation import Message
     from fabledassistant.models.rss_feed import RssItem, RssFeed
+    from fabledassistant.services.article_context import seed_article_discussion
 
     uid = get_current_user_id()
 
     async with _async_session() as session:
         result = await session.execute(
-            _select(RssItem, RssFeed.title.label("feed_title"))
+            _select(RssItem)
             .join(RssFeed, RssItem.feed_id == RssFeed.id)
             .where(RssItem.id == item_id, RssFeed.user_id == uid)
         )
-        row = result.first()
+        item = result.scalars().first()
 
-    if row is None:
+    if item is None:
         return jsonify({"error": "Article not found"}), 404
 
-    item, feed_title = row
-
     conv_title = (item.title or "Article discussion")[:80]
     conv = await create_conversation(uid, title=conv_title, conversation_type="chat")
 
-    from fabledassistant.services.rss import _fetch_full_article
-    source = feed_title or "News"
-    content_body = (await _fetch_full_article(item.url) if item.url else None) or (item.content or "").strip()
-    seeded_text = f"**{source}**\n\n**{item.title}**"
-    if content_body:
-        seeded_text += f"\n\n{content_body}"
-    if item.url:
-        seeded_text += f"\n\nSource: {item.url}"
+    model = await get_setting(uid, "default_model", "") or Config.OLLAMA_MODEL
+    discuss_prompt = await seed_article_discussion(conv.id, item, model)
 
-    async with _async_session() as session:
-        msg = Message(
-            conversation_id=conv.id,
-            role="assistant",
-            content=seeded_text,
-            msg_metadata={"rss_item_ids": [item_id]},
-        )
-        session.add(msg)
-        await session.commit()
+    # Reload conversation so we see the two messages the helper just added.
+    conv = await get_conversation(uid, conv.id)
+    assert conv is not None
 
-    return jsonify({"conversation_id": conv.id}), 201
+    history: list[dict] = []
+    for msg in conv.messages:
+        if msg.role == "system":
+            continue
+        msg_dict: dict = {"role": msg.role, "content": msg.content or ""}
+        if msg.tool_calls:
+            msg_dict["tool_calls"] = [
+                {"function": {"name": tc["function"], "arguments": tc["arguments"]}}
+                for tc in msg.tool_calls
+            ]
+            history.append(msg_dict)
+            for tc in msg.tool_calls:
+                history.append({"role": "tool", "content": json.dumps(tc.get("result", {}))})
+        else:
+            history.append(msg_dict)
+
+    assistant_msg = await add_message(conv.id, "assistant", "", status="generating")
+    buf = create_buffer(conv.id, assistant_msg.id)
+    asyncio.create_task(run_generation(
+        buf, history, model, uid, conv.id, conv.title or "", discuss_prompt,
+    ))
+
+    return jsonify({
+        "conversation_id": conv.id,
+        "assistant_message_id": assistant_msg.id,
+        "status": "generating",
+    }), 202