TUI transparency changes after resuming from Ctrl+Z (suspend/fg) #21069

Bug Description

When suspending OpenCode with Ctrl+Z and resuming with fg, the TUI gains transparency that it did not have before. This happens in Kitty terminal with transparency enabled.

Steps to Reproduce

1. Run OpenCode in Kitty with terminal transparency enabled
2. Press Ctrl+Z to suspend
3. Press fg to resume

Expected Behavior

The TUI should render identically after resuming, with no transparency changes.

Actual Behavior

After resuming, the OpenCode TUI displays transparency that was not present before suspension. This makes the UI difficult to read and visually inconsistent.

Environment

• OpenCode version: latest
• Terminal: Kitty
• OS: NixOS
• Shell: zsh

Workaround

Using tmux instead of Ctrl+Z avoids the issue entirely.