[FEATURE] When writing/editing code, allow a mode where [ESC] to have a longer conversation does not collapse the view of the proposal

Preflight Checklist

• [x] I have searched existing requests and this feature hasn't been requested yet
• [x] This is a single feature request (not multiple features)

Problem Statement

When Claude proposes a file write and the accept/reject diff UI appears, pressing ESC to dismiss it and type a comment collapses the diff entirely. The proposed code is no longer visible while the user composes their response. This makes the review flow unusable for collaborative code discussion — you cannot comment on code you cannot see.

Proposed Solution

Keep the diff panel visible (or at least scrollable/togglable) while the user types a response. The diff and the text input should be able to coexist on screen simultaneously, similar to how a GitHub PR review lets you read the diff while writing an inline comment.

Alternative Solutions

1. After ESC collapses the diff, provide a keyboard shortcut or button to re-expand it without losing the text already typed.
2. Open a split view: diff on one side, chat input on the other, so neither displaces the other.
3. At minimum, show a compact "show diff" toggle above the text input that re-displays the proposed change inline in the conversation thread.

Priority

Medium - Would be very helpful

Feature Category

CLI commands and flags

Use Case Example

A developer is reviewing a 30-line proposed edit to a C++ header. They want to ask "why did you make foo private instead of protected?" They press ESC to type the question. The diff disappears. They now have to either accept the change blind, reject it and re-ask, or ask Claude to re-show the code as plain conversation text — which defeats the purpose of the integrated diff UI entirely.

Additional Context

_No response_