Add some shell completions

[kachick]

• Add cargo-make fzf completion for zsh
• Register the makers fzf completions also in bash
• Add go-task fzf completions
• Add zellij fzf completions
• Use special filter for zellij kill-session
• Improve handling args in fzf complete hook
• Fix to register zellij bash comletions
• Split bash and zsh specific code
• Fix cdnix command with use of readlink
• Fix enabling go-task zsh and fish completions (Fix enabling go-task zsh and fish completions #770)
• Fallback bash zellij comletion to default
• Revert fzf bash completions which conflict with bash default
• Attempt to package cargo-make shell completions [WIP] [ci skip]
• Fix nix path
• Inject bash completion also in zsh
• Remove conflicting fzf bash completions
• Improve note about cargo-make zsh completions
• Attempt to delegate to source_sh for completion
• Revert "Attempt to delegate to source_sh for completion"
• Add note about cargo-make zsh completions
• Make small diff with main
• Revert "Make small diff with main"