feat(conversations): pre-SDK rows read from canonical messages, implied titles, markdown adopts them by first prompt

tests/test_routing.py

@@ -1,13 +1,14 @@
 import asyncio
 import tempfile
 from pathlib import Path
+from typing import cast
 
 import frontmatter
 import httpx
 import pytest
 
 from beaver_gateway.core.auth import TokenStore
-from beaver_gateway.core.conversation_store import load_messages
+from beaver_gateway.core.conversation_store import load_messages, rewrite_messages
 from beaver_gateway.core.gateway_tools import _tools
 from beaver_gateway.core.registry import McpRegistry
 from beaver_gateway.frontends.anthropic import AnthropicMessagesFrontend
@@ -255,3 +256,31 @@ async def test_markdown_edited_reply_reseeds_the_session(stack: Stack) -> None:
         async with stack.world.db.session() as session:
             stored = await load_messages(session, conversation_id=1)
         assert stored[1]["content"] == [{"type": "text", "text": "penguin"}]
+
+
+async def test_markdown_adopts_a_pre_sdk_conversation(stack: Stack) -> None:
+    world = stack.world
+    old = await world.conversations.create(kind="deep", agent="d", origin="markdown")
+    async with world.db.session() as session:
+        await rewrite_messages(
+            session,
+            conversation_id=cast("int", old.id),
+            messages=[
+                {"role": "user", "content": "hello"},
+                {"role": "assistant", "content": "ok:hello"},
+            ],
+        )
+    content = "### User:\n\nhello\n\n---\n\n### Assistant:\n\nok:hello\n\n---\n\n### User:\n\nnext\n"
+    async with stack.client(stack.markdown) as c:
+        r = await c.post(
+            "/chat",
+            json={"filename": "old.md", "agent": "d", "content": content},
+            headers=AUTH,
+        )
+    assert r.status_code == 200, r.text
+    assert f"conversation_id: {old.external_id}" in r.json()["new_content"]
+    assert len(await world.conversations.find(kind="deep")) == 1
+    bindings = await world.conversations.bindings(old)
+    assert [(b.frontend, b.external_id) for b in bindings] == [("markdown", "old.md")]
+    assert ScriptedClient.instances[-1].prompts == ["next"]
+    assert "ok:hello" in repr(vars(world.store))