* fix(preflight): resolve WSL/SSH agent paths past shell aliases
LeanCTX and similar tools wrap claude/codex as interactive shell aliases.
command -v then returns alias text, which fails absolute-path detection and
hides installed agents (#7816).
Prefer bash type -P, then zsh type -p, then command -v for dash/sh fallback
in WSL agent discovery, WSL isCommandOnPath, and remote relay probes.
* fix(preflight): harden alias-safe PATH lookup chain
Require non-empty results between type -P, type -p, and command -v so bash
type -p empty success cannot skip later lookups.
* fix(preflight): resolve agent executables directly from PATH
---------
Co-authored-by: Jinwoo Hong <73622457+Jinwoo-H@users.noreply.github.com>
