feat: group_node schema + projector handlers

chat/state/group_node.py

@@ -0,0 +1,50 @@
+from __future__ import annotations
+import json
+from sqlite3 import Connection
+from chat.eventlog.projector import on
+from chat.eventlog.log import Event
+
+
+@on("group_node_initialized")
+def _apply_group_node_initialized(conn: Connection, e: Event) -> None:
+    p = e.payload
+    conn.execute(
+        "INSERT OR REPLACE INTO group_node "
+        "(chat_id, members_json, summary, dynamic, threads_json) "
+        "VALUES (?, ?, ?, ?, ?)",
+        (
+            p["chat_id"],
+            json.dumps(p["members"]),
+            p.get("summary", ""),
+            p.get("dynamic", ""),
+            json.dumps(p.get("threads", [])),
+        ),
+    )
+
+
+@on("group_node_updated")
+def _apply_group_node_updated(conn: Connection, e: Event) -> None:
+    p = e.payload
+    conn.execute(
+        "UPDATE group_node SET summary = ?, dynamic = ?, updated_at = datetime('now') "
+        "WHERE chat_id = ?",
+        (p.get("summary", ""), p.get("dynamic", ""), p["chat_id"]),
+    )
+
+
+def get_group_node(conn: Connection, chat_id: str) -> dict | None:
+    row = conn.execute(
+        "SELECT chat_id, members_json, summary, dynamic, threads_json, updated_at "
+        "FROM group_node WHERE chat_id = ?",
+        (chat_id,),
+    ).fetchone()
+    if not row:
+        return None
+    return {
+        "chat_id": row[0],
+        "members": json.loads(row[1]),
+        "summary": row[2],
+        "dynamic": row[3],
+        "threads": json.loads(row[4]),
+        "updated_at": row[5],
+    }