fzf-pick prop find's key/value when not supplied
tsk prop find — fzf-pick key, then value (with <any> to skip)
tsk prop find KEY — list every task with KEY set (existing semantics)
tsk prop find KEY VAL — direct match (existing)
Mirrors the recent prop set ergonomics. The <any> sentinel in the
value picker means "match any value for this key" so the user can
still narrow on key alone via fzf.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>