Added opt-in canonical observer polling lifecycle

server/market/postgres-custody.ts

@@ -104,6 +104,7 @@ export class PostgresCustody {
     return { enabled: true, mode: 'sandbox', policy: CUSTODY_POLICY, network: NETWORK, chainId: CHAIN_ID,
       custodianId: this.id, feeBps: this.options.feeBps, ...resolvedMarketPolicy(this.options), liveDeposits: false, liveWithdrawals: false, nftSettlement: false };
   }
+  get rehearsalObserverEnabled(): boolean { return this.options.disposableSaleRehearsal === true; }
   private async transaction<T>(write: boolean, fn: (c: PoolClient) => Promise<T>): Promise<T> {
     check(this.active < 16, 'Custody database busy; retry the original command shortly');
     this.active++;