[BUG] Remaining context percentage no longer represents actuality

Environment

• Platform (select one):
• [ x] Anthropic API (CLI/TUI)
• Claude CLI version: 1.0.9
• Operating System: mac
• Terminal: ghostty/zsh

Important detail: I am in manual /compact mode (not auto)

Bug Description

The percentage is wrong. I get consistent failures now before reaching 0.
I can no longer send any message other than my /compact (which works, but this is annoying as I tend to have strategic compact strategy in conjunction with how I have the agents manage context and task progress).

<img width="888" alt="Image" src="https://github.com/user-attachments/assets/3579bdde-0128-4289-ba72-e173d33ad9bf" />