Replication places subscriptions and record-lock ownership on isolated application workers #974

Problem

Replication subscriptions and record-lock ownership can be placed on an isolated application's dedicated worker.

Isolated-application workers (HarperFast/harper#2524, shipped in 5.3.0) are started with name: THREAD_TYPES.HTTP (core server/threads/socketRouter.ts:276). Replication is a trusted built-in, so placedOnThisThread loads it on every worker, isolated ones included (core components/componentLoader.ts:178-179). harper-pro picks placement targets with workers.filter((worker) => worker.name === 'http') in four places, none of which exclude worker.application:

• replication/subscriptionManager.ts:1427 (re-drive / rebinding)
• replication/subscriptionManager.ts:1699 (connectToNextWorker → placeSubscription)
• replication/subscriptionManager.ts:1798 (reconcileWorkers)
• replication/recordLockTransport.ts:962 (httpWorkers() for lock ownership)

Impact

• Replication apply, and the sending on that worker's inbound sockets, runs on the event loop the operator dedicated to one application. This defeats the isolation the operator configured.
• Restarting that application's worker (scoped restart) drops the replication connections and lock ownership it holds. Recovery then goes through the worker-exit path and reconnect for an unrelated cause.

Fix

Exclude workers with worker.application set from replication placement. Ideally do it through one shared selector, which is also the seam #435's replication pool needs.

🤖 Claude Opus 5.5 on behalf of Kris.