Warp SSH hangs on Coder hosts when ble.sh loads

Problem

SSH sessions to *.coder hosts hang under Warp Terminal when the legacy SSH wrapper is enabled.

Example:

ssh pi.coder -vvv

The same host works with normal non-interactive SSH and with Warp's legacy wrapper disabled.

What Warp is doing

Warp rewrites the SSH command into a wrapper sequence similar to:

ssh \
  -o ControlMaster=yes \
  -o ControlPath=~/.ssh/<session-id> \
  -t pi.coder '<bootstrap>; exec "$SHELL" -l'

The bootstrap exports Warp variables, emits the OSC hook, then starts a login shell:

export TERM_PROGRAM='WarpTerminal'
export WARP_IS_SSH='1'
export WARP_CLIENT_VERSION='v0.2026.05.20.09.21.stable_03'
export WARP_CLI_AGENT_PROTOCOL_VERSION='1'
printf '\033]9278;d;%s' "$hook"
exec "$SHELL" -l

Root cause

The hang is not in Coder SSH transport or Warp's hook emission. Manual replay showed the session reaches:

MARK before_exec shell=/bin/bash
+ exec /bin/bash -l

Then remote bash startup loads ble.sh from /etc/bash.bashrc:

[[ $- == *i* ]] && source -- /usr/local/share/blesh/ble.sh --attach=prompt

ble.sh blocks during terminal probing under Warp's SSH wrapper and shows:

[ble: press RET to continue]

Fix applied on pi.coder

Guard ble.sh so it does not load for Warp SSH sessions:

### hakim-blesh-start
# ble.sh
if [[ $- == *i* && ${TERM_PROGRAM:-} != WarpTerminal && -z ${WARP_IS_SSH:-} ]]; then
  source -- /usr/local/share/blesh/ble.sh --attach=prompt
fi
### hakim-blesh-end

Backup made on host:

/etc/bash.bashrc.bak-warp-ble-20260524145119

Verification

Before fix:

[ble: press RET to continue]

After fix, the Warp-like bootstrap starts the login shell and accepts input:

coder@coder-shekohex-pi:~$ exit
logout
STATUS=EXITED:0

Notes

Unrelated noisy issues observed during debugging:

LC_CTYPE: cannot change locale (UTF-8)
version mismatch: client v2.33.0+f009c17, server v2.31.10+e58ecf5