[BUG] Subtask fails to return to parent task after manual pause and resume during API hang

[myk1yt]

Problem (one or two sentences)

When a subtask hangs due to API provider server issues and is manually paused and resumed, it fails to return
control to the parent task upon completion. The link between the parent and child tasks seems to be lost during
the stop/resume lifecycle.

Context (who is affected and when)

Users using subtasks/subagent features (such as Orchestrator mode) when experiencing API response freezes
(specifically with DeepSeek V4 Pro), who manually stop and resume the task to recover the session.

Reproduction steps

1. Start a parent task and let it delegate a subtask.
2. During the subtask execution, wait for the API call to hang (due to DeepSeek V4 Pro server response
   delay/freeze).
3. Manually click the "Stop" button in the extension UI to cancel the hanging task.
4. Click the "Resume" button to restart/resume the task.
5. Let the subtask finish its work and call the completion tool ( attempt_completion / finishSubTask ).

Expected result

The subtask successfully completes and automatically hands control back to the parent task, allowing the parent task to resume.

Actual result

The subtask finishes, but it does not return to the parent task. The parent task remains paused/stuck, and the subtask behaves as if it is a standalone task with no parent.

Variations tried (optional)

• Currently, different APIs are configured for different modes, so it is unclear if this contributes to the
issue.
• Note: I have manually patched and resolved issue #457 on my local version, so it is highly unlikely to be the
cause of this issue.

App Version

3.58.1

API Provider (optional)

DeepSeek

Model Used (optional)

DeepSeek V4 Pro

Zoo Code Task Links (optional)

No response

Relevant logs or errors (optional)

[huankimtran]

Hi team, looking forward to this fix. Confirmed things were working fine in 3.56 and failing in 3.58

[edelauna]

Tracked by [Epic 2] Task Lifecycle Fixes (#357).

This bug depends on Story 2.3 (task status transition guard + startup reconciliation) landing first — that story adds the startup reconciliation pass that detects a parent stuck in delegated state and repairs the parent-child link after an interrupted delegation. Until 2.3 ships, the parent-child relationship lost during a manual stop/resume cannot be automatically recovered.