Work Intent: Repair and fully verify arraySubscription event payloads

Overview

Fix the confirmed arraySubscription GraphQL event payload mismatch reported in #2056. The resolver exposes arraySubscription, but the event listener currently publishes { array }, causing non-null subscription failures when an update is emitted.

No implementation work will begin until this Work Intent is approved.

Technical Approach

• Create a focused branch from current main.
• Change the array event publisher to emit the GraphQL subscription root field expected by the resolver.
• Add a regression test that exercises the publisher/resolver contract, not merely resolver construction.
• Prefer an end-to-end GraphQL subscription test that subscribes, publishes an array update, and asserts a complete non-null payload.
• Preserve the regular array query and existing array event timing/debouncing behavior.
• Run pnpm --filter ./api test, API lint, API type-check, and the repository build.
• Build and deploy a test artifact to a controlled Unraid 7.3.2 target.
• Subscribe through the real GraphQL WebSocket endpoint, trigger a real array event, and prove the former non-null error is replaced by a valid arraySubscription payload.
• Re-run representative working subscriptions to guard against shared pub/sub regressions.

A PR will only be submitted if repository tests and the live end-to-end proof all pass. If the live proof cannot be completed safely and conclusively, no fix PR will be opened.

Scope

• API
• Plugin
• Web UI
• Build/Deploy Process
• Documentation

Timeline & Impact

• Estimated time needed: 1-2 focused development sessions after approval
• Potential impacts: Array subscription clients only. No array mutations or lifecycle behavior will be changed.

Pre-submission Checklist

• I have searched for similar work/issues
• I understand this needs approval before starting
• I am willing to make adjustments based on feedback

No file paths are named; start by locating the array event publisher, the arraySubscription resolver, and existing API subscription tests. Run the API tests, lint, type-check, and repository build; done requires a complete non-null subscription payload, preserved array behavior, and the specified live WebSocket proof.