Support deleting AI messages and subsequent nodes

[XiaoYingYo]

Problem (one or two sentences)

Currently, there is no way to delete an AI message and all its subsequent branches. This cannot add user messages after a certain node, or change subsequent steps.

Context (who is affected and when)

All users are affected. This is a general usability issue that makes it difficult to manage the conversation flow.

Constraints / preferences (optional)

No response

Request checklist

• I've searched existing Issues and Discussions for duplicates
• This describes a specific problem with clear context and impact

Roo Code Task Links (optional)

No response

Acceptance criteria (optional)

No response

Proposed approach (optional)

No response

Trade-offs / risks (optional)

No response

[roomote]

I'm exploring a potential fix for this feature request and will open a PR to share progress. This would add the ability to delete AI messages along with all their subsequent nodes in the conversation flow.

[roomote]

I've opened PR #9036 with my attempt at addressing this issue: #9036

The implementation adds delete functionality to AI messages (text, API requests, and completion results) with both click and right-click support, matching the existing UX for user message deletion. All subsequent messages are removed when an AI message is deleted, as requested.

Feedback welcome!

[XiaoYingYo]

@roomote
It should not be done by clicking or right-clicking. I see there is a copy button next to the AI message. Can we add a new delete button next to the copy button?

[roomote]

I've seen your clarification about adding a delete button next to the copy button instead of using click/right-click. I'll explore implementing this approach to match the existing UI pattern.