trystub 1.2.0

Added

• Operator actions on StubClient. stub.sweep() reclaims reservations left held past the
  server's RESERVATION_TTL_SECONDS; stub.provisionShards(accountId, shards?) splits an
  account's current balance across shard rows for throughput. Both are operator-only: construct
  the client with the server's ADMIN_TOKEN as apiKey, not an agent's scoped key.
• Stub server: reservation TTL sweep. A held reservation nobody ever settles or releases
  (a crashed agent) is reclaimed automatically past RESERVATION_TTL_SECONDS (default 900s), via
  npm run sweep or the new admin-gated POST /api/sweep. Idempotent: contends on the reservation
  row under OCC exactly like a normal release(), so it can never double-refund a hold another
  process is settling.

Fixed

• Stub server: sharded accounts now enforce the same policy as everyone else. A sharded budget
  account previously skipped the frozen check, the policy engine, the velocity breaker, and
  ancestor hierarchy caps entirely — only the shard-level cap was enforced. Fixed to match the
  plain spend path exactly; /api/spend now dispatches to the sharded path automatically for any
  account provisioned with provisionShards.