feat: per-task model/effort/approval + relay models endpoint (#59)

Co-authored-by: host <host@test.local>

cloud/db.py

@@ -831,6 +831,9 @@ POSTGRES_SCHEMA = (
     "goal TEXT, "
     "verify_command TEXT, "
     "goal_max_rounds INTEGER, "
+    "model TEXT, "
+    "effort TEXT, "
+    "approval TEXT, "
     "UNIQUE(project_id, idempotency_key))",
     "CREATE INDEX IF NOT EXISTS idx_tasks_status ON tasks(status)",
     "CREATE TABLE IF NOT EXISTS summaries("