Sub-sessions triggered by a parent session in plan mode no longer respect th...

Sub-sessions triggered by a parent session in plan mode no longer respect the "Plan approval" gate. Instead, agents automatically start implementation.

This seem a natural behaviour for sub-sessions, as they are managed by a parent session. However, it is weird to have the plan mode ask for user confirmation while the session is already working on the implementation.

Idea: Include a flag on which parent sessions can allow plan auto-approve. If "true", sessions started in plan mode are automatically approved (no user prompt) and continue with the recommended implementation mode. If "false", the child session will stop and wait of human review/approval of the plan.

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| Field | Value |
| --- | --- |
| App version | 1.0.26 |
| OS | macOS 26.5.2 |
| Theme | GitHub |
| Path | /chat |
| Tenure | Week 11 |

The issue names the parent-session plan-approval flow and the sub-session creation path, but no files or tests. Start by tracing how child sessions handle plan approval; done means a parent-controlled setting determines whether child plans auto-approve or wait for human review, with coverage for both choices.

Written by the indexing model from the issue text.