feat: migrate from docopt to cobra for CLI argument parsing

Replace docopt-go with spf13/cobra, giving cheat a built-in
`--completion` flag that dynamically generates shell completions for
bash, zsh, fish, and powershell. This replaces the manually-maintained
static completion scripts and resolves the root cause of multiple
completion issues (#768, #705, #633, #632, #476).

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

scripts/cheat.bash

@@ -1,74 +0,0 @@
-# cheat(1) completion                                      -*- shell-script -*-
-
-# generate cheatsheet completions, optionally using `fzf`
-_cheat_complete_cheatsheets()
-{
-  if [[ "$CHEAT_USE_FZF" = true ]]; then
-    FZF_COMPLETION_TRIGGER='' _fzf_complete "--no-multi" "$@" < <(
-      cheat -l | tail -n +2 | cut -d' ' -f1
-    )
-  else
-    COMPREPLY=( $(compgen -W "$(cheat -l | tail -n +2 | cut -d' ' -f1)" -- "$cur") )
-  fi
-}
-
-# generate tag completions, optionally using `fzf`
-_cheat_complete_tags()
-{
-  if [ "$CHEAT_USE_FZF" = true ]; then
-    FZF_COMPLETION_TRIGGER='' _fzf_complete "--no-multi" "$@" < <(cheat -T)
-  else
-    COMPREPLY=( $(compgen -W "$(cheat -T)" -- "$cur") )
-  fi
-}
-
-# implement the `cheat` autocompletions
-_cheat()
-{
-  local cur prev words cword split
-  _init_completion -s || return
-
-  # complete options that are currently being typed: `--col` => `--colorize`
-  if [[ $cur == -* ]]; then
-    COMPREPLY=( $(compgen -W '$(_parse_help "$1" | sed "s/=//g")' -- "$cur") )
-    [[ $COMPREPLY == *= ]] && compopt -o nospace
-    return
-  fi
-
-  # implement completions
-  case $prev in
-    --colorize|-c|\
-    --directories|-d|\
-    --init|\
-    --regex|-r|\
-    --search|-s|\
-    --tags|-T|\
-    --version|-v)
-      # noop the above, which should implement no completions
-      ;;
-    --edit|-e)
-      _cheat_complete_cheatsheets
-      ;;
-    --list|-l)
-      _cheat_complete_cheatsheets
-      ;;
-    --path|-p)
-      COMPREPLY=( $(compgen -W "$(cheat -d | cut -d':' -f1)" -- "$cur") )  
-      ;;
-    --rm)
-      _cheat_complete_cheatsheets
-      ;;
-    --tag|-t)
-      _cheat_complete_tags
-      ;;
-    *)
-      _cheat_complete_cheatsheets
-      ;;
-  esac
-
-  $split && return
-
-} &&
-complete -F _cheat cheat
-
-# ex: filetype=sh

scripts/cheat.fish

@@ -1,13 +0,0 @@
-complete -c cheat -f -a "(cheat -l | tail -n +2 | cut -d ' ' -f 1)"
-complete -c cheat -l init -d "Write a default config file to stdout"
-complete -c cheat -s c -l colorize -d "Colorize output"
-complete -c cheat -s d -l directories -d "List cheatsheet directories"
-complete -c cheat -s e -l edit -x -a "(cheat -l | tail -n +2 | cut -d ' ' -f 1)" -d "Edit cheatsheet"
-complete -c cheat -s l -l list -d "List cheatsheets"
-complete -c cheat -s p -l path -x -a "(cheat -d | cut -d ':' -f 1)" -d "Return only sheets found on given path"
-complete -c cheat -s r -l regex -d "Treat search phrase as a regex"
-complete -c cheat -s s -l search -x -d "Search cheatsheets for given phrase"
-complete -c cheat -s t -l tag -x -a "(cheat -T)" -d "Return only sheets matching the given tag"
-complete -c cheat -s T -l tags -d "List all tags in use"
-complete -c cheat -s v -l version -d "Print the version number"
-complete -c cheat -l rm -x -a "(cheat -l | tail -n +2 | cut -d ' ' -f 1)" -d "Remove (delete) cheatsheet"

scripts/cheat.zsh

@@ -1,65 +0,0 @@
-#compdef cheat
-
-local cheats taglist pathlist
-
-_cheat_complete_personal_cheatsheets()
-{
-  cheats=("${(f)$(cheat -l -t personal | tail -n +2 | cut -d' ' -f1)}")
-  _describe -t cheats 'cheats' cheats
-}
-
-_cheat_complete_full_cheatsheets()
-{
-  cheats=("${(f)$(cheat -l | tail -n +2 | cut -d' ' -f1)}")
-  _describe -t cheats 'cheats' cheats
-}
-
-_cheat_complete_tags()
-{
-  taglist=("${(f)$(cheat -T)}")
-  _describe -t taglist 'taglist' taglist
-}
-
-_cheat_complete_paths()
-{
-  pathlist=("${(f)$(cheat -d | cut -d':' -f1)}")
-  _describe -t pathlist 'pathlist' pathlist
-}
-
-_cheat() {
-
-  _arguments -C \
-    '(--init)--init[Write a default config file to stdout]: :->none' \
-    '(-c --colorize)'{-c,--colorize}'[Colorize output]: :->none' \
-    '(-d --directories)'{-d,--directories}'[List cheatsheet directories]: :->none' \
-    '(-e --edit)'{-e,--edit}'[Edit <sheet>]: :->personal' \
-    '(-l --list)'{-l,--list}'[List cheatsheets]: :->full' \
-    '(-p --path)'{-p,--path}'[Return only sheets found on path <name>]: :->pathlist' \
-    '(-r --regex)'{-r,--regex}'[Treat search <phrase> as a regex]: :->none' \
-    '(-s --search)'{-s,--search}'[Search cheatsheets for <phrase>]: :->none' \
-    '(-t --tag)'{-t,--tag}'[Return only sheets matching <tag>]: :->taglist' \
-    '(-T --tags)'{-T,--tags}'[List all tags in use]: :->none' \
-    '(-v --version)'{-v,--version}'[Print the version number]: :->none' \
-    '(--rm)--rm[Remove (delete) <sheet>]: :->personal' 
-
-  case $state in
-    (none)
-      ;;
-    (full)
-      _cheat_complete_full_cheatsheets
-      ;;
-    (personal)
-      _cheat_complete_personal_cheatsheets
-      ;;
-    (taglist)
-      _cheat_complete_tags
-      ;;
-    (pathlist)
-      _cheat_complete_paths
-      ;;
-    (*)
-      ;;
-  esac
-}
-
-compdef _cheat cheat