[Bug] Conversation history lost after v2.1.90 update; context window and prompt suggestions malfunction

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Bug Description

After updating to v2.1.90 (now on v2.1.91), I'm experiencing multiple regressions that significantly degrade the CLI experience:

1. Conversation history lost / unable to scroll

• The entire conversation history in the terminal is no longer scrollable
• I cannot scroll up to review earlier parts of the conversation
• This started immediately after the v2.1.90 update

1. Prompt suggestions broken

• The prompt suggestion feature is malfunctioning — suggestions either don't appear or behave incorrectly

1. Context window issues

• The terminal's context window appears to be clearing or resetting unexpectedly
• Previously retained context is lost mid-session

1. Overall quality degradation

• Noticeable decline in execution quality and reliability since the update

Steps to Reproduce

1. Update Claude Code to v2.1.90 or v2.1.91
2. Start a new conversation in the VS Code terminal
3. After several exchanges, attempt to scroll up — history is missing
4. Observe prompt suggestions failing to render correctly

Expected Behavior

• Full conversation history should remain scrollable in the terminal
• Prompt suggestions should work as they did prior to v2.1.90
• Context window should persist throughout the session

Environment

• OS: Windows 11 Pro (10.0.26100)
• Terminal: VS Code integrated terminal
• Shell: bash
• Claude Code version: 2.1.91 (regression started in 2.1.90)
• Feedback ID: 15fbcf87-c3a5-4fe2-894a-b0c23f5abc40