[BUG] Plan rejection reason text not displayed in conversation history

Environment

• Platform: VSCode Extension
• Claude Code version: 2.0.5
• Operating System: macOS 15.6.1
• Terminal/IDE: VSCode

Bug Description

When rejecting a plan in plan mode and providing a written reason for the rejection, the text that the user writes does not appear in the conversation history at all. This makes it difficult to reference what was said during the rejection and creates a confusing conversation flow where the user's input seems to disappear.

Steps to Reproduce

1. Enter plan mode (Shift+Tab twice)
2. Request a plan for some task
3. When prompted to accept/reject the plan, choose "No" and provide a written reason
4. The rejection reason text does not appear in the conversation history

Expected Behavior

The user's rejection reason should be visible in the conversation history, just like any other user input.

Actual Behavior

The rejection reason text completely disappears from the conversation history - it's as if the user never wrote anything.

Additional Context

• Related to #3226 (rejected plans disappearing), but this is a distinct issue about user input disappearing
• Unclear if the rejection reason is being saved internally but just not displayed, or if it's being lost entirely
• This creates a poor user experience as users cannot see what they previously wrote when explaining why a plan was rejected