Suspending Droid (ctrl+z) leaves terminal in CSI-u keyboard mode, breaking shell keybindings.

[MaicoTimmerman]

When suspending the CLI with Ctrl-Z, the terminal is left in CSI-u keyboard mode. After the process is suspended, the shell receives CSI-u encoded key sequences instead of normal control characters, causing keybindings like Ctrl-E to appear as literal escape sequences.

For example, pressing Ctrl-E after suspending shows:

01;5u

instead of moving the cursor to the end of the line. This breaks normal shell interaction until the terminal keyboard mode is manually reset.

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Steps to reproduce:

1. Start droid
2. Press Ctrl-Z to suspend it
3. Back in the shell, press Ctrl-E

Actual behavior:

The shell prints literal escape sequences:

01;5u

Expected behavior:

The shell should interpret Ctrl-E normally (move cursor to end of line).

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Root cause:

The CLI enables CSI-u keyboard mode (ESC [ > 1 u) but does not disable it (ESC [ < u) when receiving SIGTSTP. Terminal keyboard mode persists after process suspension.

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Workaround:

Running the following restores normal behavior:

printf '\033[<u'  # send escape code
reset             # reinitializes terminal

However, resuming droid leaves it in broken state, because the expected bindings do not work.

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Suggested fix:

Disable CSI-u keyboard mode on suspend (SIGTSTP) and re-enable it on resume (SIGCONT).

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Environment:

• Terminal: xterm-ghostty|ghostty|Ghostty
• Shell: zsh
• OS: MacOS 26.2 (25C56)
• CLI version: 0.57.17

[factory-davidgu]

@MaicoTimmerman thanks a lot for the report, we will work on a fix.

While we ship this bug fix, you can type reset+<enter> in your shell after you press Ctrl-Z and that should make keybindings like Ctrl-E work again.