Minor cleanups

Migrate some uses of assert to stdlib

Remove unnecessary logging

Tweak README

Completions documentation, script installation, fix hidden subcommands

Update badges

Work around more madness

Work around absence of reasonable process to use Go 1.23

Try alpine edge

Try golang image instead of alpine

Add sourcehut build

Add some comments, fix test failures

Move foundational completion types into root package

Separate package for bash completion

Bash completions

Ensure grim hacks are possible

Go 1.23

Make cmdstr parser behaviour somewhat more consistent with actual shell

Starting to draft bash completion

Check errors with errors.Is