feat(matrix): land QA follow-ups and refresh docs

- harden Matrix onboarding/chat lifecycle after manual QA
- refresh README and Matrix docs to match current behavior
- add local ignores for runtime artifacts and include current planning/report docs

Closes #7
Closes #9
Closes #14

adapter/matrix/bot.py

@@ -14,6 +14,7 @@ from nio import (
     RoomMemberEvent,
     RoomMessageText,
 )
+from nio.responses import SyncResponse
 from dotenv import load_dotenv
 
 from adapter.matrix.converter import from_room_event
@@ -115,12 +116,20 @@ class MatrixBot:
                 self.runtime.platform,
                 self.runtime.store,
                 self.runtime.auth_mgr,
+                self.runtime.chat_mgr,
             )
 
     async def _send_all(self, room_id: str, outgoing: list[OutgoingEvent]) -> None:
         for event in outgoing:
             await send_outgoing(self.client, room_id, event, store=self.runtime.store)
 
+
+async def prepare_live_sync(client: AsyncClient) -> str | None:
+    response = await client.sync(timeout=0, full_state=True)
+    if isinstance(response, SyncResponse):
+        return response.next_batch
+    return None
+
 async def send_outgoing(
     client: AsyncClient,
     room_id: str,
@@ -197,6 +206,8 @@ async def main() -> None:
     elif password:
         await client.login(password=password, device_name="surfaces-bot")
 
+    since_token = await prepare_live_sync(client)
+
     bot = MatrixBot(client, runtime)
     client.add_event_callback(bot.on_room_message, RoomMessageText)
     client.add_event_callback(bot.on_member, (InviteMemberEvent, RoomMemberEvent))
@@ -209,7 +220,7 @@ async def main() -> None:
         request_timeout=client_config.request_timeout,
     )
     try:
-        await client.sync_forever(timeout=30000)
+        await client.sync_forever(timeout=30000, since=since_token)
     finally:
         await client.close()