- config.fish: add ~/.fzf/bin to PATH for git-installed fzf
- config.fish: prefer fzf --fish | source (fzf >= 0.48, always
version-matched) with fallback to integrations/fzf.fish for
older builds; erase plugin bindings reliably when fzf is absent
- functions/fzf-update.fish: install or upgrade fzf from git HEAD
using --bin so shell config files are not modified