[Epic] E5: Durable triggers and event lifecycle #8200

Program: #8194
Parent: #8194
Planning ID: E5

Features

• F5.1: Webhook routing, verification, subscription provisioning, and renewal.
• F5.2: Durable polling with cursors, leases, pagination, and fair scheduling.
• F5.3: Deduplication, durable ingestion, recovery, and operational health.

Key acceptance

• Tenant routing uses trusted subscription/connection records rather than trusting payload tenant IDs.
• Events are acknowledged according to a documented durable-ingestion policy.
• Duplicate/reordered events, missed renewal, crash/restart, invalid signatures, and provider downtime have defined handling.
• Workflow publish/unpublish, connection revocation, and tenant deletion reconcile subscriptions and polling jobs.
• Delivery guarantees and reconciliation behavior are explicit; deduplication is not described as exactly-once external side effects.
• Health signals identify stalled polling, expired subscriptions, lag, and repeated failures.

Exit: webhook and polling scenarios survive restart, isolation, duplicate-delivery, and renewal tests.

Execution

Planning container. Follow AGENTS.md and existing test/ and doc/adr/ conventions. Detailed tasks follow prerequisite findings. Child links and separate dependencies are tracked below.

Hierarchy: native parent/sub-issue relationships verified on 2026-09-23. Explicit blocking dependencies are configured separately; Markdown links remain references. See #8194.

Children

• [Feature] F5.1: Webhook routing, verification, subscription provisioning, and renewal #8227 — Webhook routing, verification, subscription provisioning, and renewal
• [Feature] F5.2: Durable polling with cursors, leases, pagination, and fair scheduling #8228 — Durable polling with cursors, leases, pagination, and fair scheduling
• [Feature] F5.3: Deduplication, durable ingestion, recovery, and operational health #8229 — Deduplication, durable ingestion, recovery, and operational health

Dependencies (separate from hierarchy)

• [Epic] E0: Program initialization and current-state audit #8195 — prerequisite evidence; discovery may overlap.