bug: fish autocompletions not available

[srobroek]

What happened?

Fish autocompletions do not work, despite the documentation stating that it is.

Steps to reproduce

structkit completion install fish                                                                                                                                                                          [⏱ 1s]
Detected shell: fish

# Install shtab (once, in your environment):
python -m pip install shtab

# Generate static fish completion for 'struct':
mkdir -p ~/.config/fish/completions
structkit --print-completion fish > ~/.config/fish/completions/structkit.fish

# Apply now:
fish -c 'source ~/.config/fish/completions/structkit.fish'

Tip: You can also print completion directly via: structkit --print-completion <shell>

--- 

mkdir -p ~/.config/fish/completions
structkit --print-completion fish > ~/.config/fish/completions/structkit.fish
fish -c 'source ~/.config/fish/completions/struct.fish'

Expected behavior

Autocompletions to be generated to my fish completions dir.

Actual behavior

structkit: error: argument --print-completion: invalid choice: 'fish' (choose from bash, zsh, tcsh))

Environment

Structkit Version: 3.2.1

• Python version: 3.14
• OS: MacOS 26.3