fix: spec_events.py — get_pool → get_conn, remove FOR UPDATE

site/db/spec_events.py

@@ -1,6 +1,6 @@
 """spec_events — event sourcing: apply ops, reset contract."""
 import json, uuid
-from db.connection import query, execute, get_pool
+from db.connection import query, execute, get_conn
 
 
 def reset(contract_id):
@@ -10,26 +10,14 @@ def reset(contract_id):
 
 
 def get_next_seq(contract_id):
-    """Get next sequence number with row lock to prevent race conditions."""
-    pool = get_pool()
-    conn = pool.getconn()
-    try:
-        conn.autocommit = False
-        with conn.cursor() as cur:
-            cur.execute(
-                "SELECT seq FROM spec_events WHERE contract_id = %s ORDER BY seq DESC LIMIT 1 FOR UPDATE",
+    """Get next sequence number. WAL serializes writers — no explicit lock needed."""
+    conn = get_conn()
+    cur = conn.execute(
+        "SELECT seq FROM spec_events WHERE contract_id = ? ORDER BY seq DESC LIMIT 1",
         (contract_id,),
     )
     row = cur.fetchone()
-            seq = (row[0] + 1) if row else 1
-        conn.commit()
-        return seq
-    except Exception:
-        conn.rollback()
-        raise
-    finally:
-        conn.autocommit = True
-        pool.putconn(conn)
+    return (row["seq"] + 1) if row else 1
 
 
 def apply_ops(contract_id, supplement_id, document_id, ops, prompt_id, raw_llm_response):