[General] Need manually controlled checkpointing at each turn, restore ability and fork ability.

**Mood:** 😔
**Category:** General

Need manually controlled checkpointing at each turn, restore ability and fork ability. Why is every Github Copilot experience except the one in VS Code missing this most basic and useful functionality? It should be the first thing added.

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| Field | Value |
| --- | --- |
| App version | 1.0.0 |
| OS | Windows 10.0.26100 |
| Theme | Noctis Azureus |
| Path | /chat |
| Tenure | Week 2 |

Start with the /chat experience, the only entry point named in the issue, and trace how turns and conversation state are currently handled. No files or tests are identified; done would require agreed behavior for manually creating checkpoints, restoring them, and forking a conversation.

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