TECH-4 · SLA + automatic task owner beyond an idle threshold

> Product/tech item from the dimensional diagnosis (**2026-07-03, v2**, section C).

### Finding
Stuck tasks have no automatic owner or expiry — this is the technical "how" behind PROC-2b.

### Action
Mechanism for **SLA + automatic owner** of a task idle beyond a threshold. *(Product/Org)*

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- **Priority:** 🔴 High
- **Dependencies:** INST-4 (#2494). Backs PROC-2b.
- **Epic:** #2503

The issue names no files, tests, or entry points. Start by reading dependency INST-4 (#2494), epic #2503, and PROC-2b to establish the existing task flow; done means a defined mechanism for an idle threshold, automatic owner, SLA, and expiry.

Scritto dal modello di indicizzazione a partire dal testo della issue.