Delegated sessions are not renamed with a representative identifier in Codex #283

Description:
When Codex Companion delegates tasks, the resulting sessions appear in the Codex session list with the generic name Codex Companion Task: <task> l... instead of replacing <task> with an actual representative identifier.

Current behavior:
All delegated sessions show identical, unresolved names like Codex Companion Task: <task> l..., making them indistinguishable from each other.

Expected behavior:
Each session should display a meaningful name such as Codex Companion Task: fix-auth-bug or Codex Companion Task: #1234, so the user can identify each task at a glance.

Impact:
When multiple tasks are running in parallel (as shown in the screenshot, up to 5 simultaneous sessions), it is impossible to tell them apart without opening each one individually.

Possible cause:
The <task> placeholder is not being interpolated when naming the session, or the task identifier is not being passed correctly at session creation time.

Steps to reproduce:

1. Delegate 2 or more tasks using Codex Companion
2. Observe the active sessions list in Codex