Feature/shell completion

[404Simon]

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Description

Adds a completion command that generates shell completion scripts for bash, zsh, and fish, enabling tab-completion for all pangolin CLI commands and flags.

How to test?

# Test bash completion generation
pangolin completion bash
# Test zsh completion generation  
pangolin completion zsh
# Test fish completion generation
pangolin completion fish
# Verify completions work (bash example)
source <(pangolin completion bash)
pangolin <TAB><TAB>

[Copilot]

Pull request overview

This PR adds shell completion support for the Pangolin CLI, enabling tab-completion for bash, zsh, and fish shells. The implementation provides a custom completion command that generates appropriate completion scripts for each supported shell.

Key Changes

• Added custom completion command with subcommands for bash, zsh, and fish
• Updated github.com/fosrl/newt dependency from v0.0.0 to v1.8.0
• Added comprehensive documentation for shell completion setup

Reviewed changes

Copilot reviewed 5 out of 6 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
cmd/completion/completion.go	New completion command implementation that generates shell-specific completion scripts
cmd/root.go	Integrates completion command into root CLI and removes default hidden completion options
go.mod	Updates newt dependency to v1.8.0 and moves spf13/pflag to indirect dependencies
go.sum	Adds dependency checksums for newt v1.8.0 and updates google/go-cmp to v0.7.0
docs/pangolin_completion.md	New documentation with installation instructions for all supported shells
docs/pangolin.md	Updates root documentation to reference new completion command

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[water-sucks]

To my knowledge, the pangolin completion command already exists.

It is also being used in generation of completion scripts when building in the nixpkgs repository, as shown here: https://github.com/NixOS/nixpkgs/blob/3017d2b27b532d627c396a5351bee1c9d0e8b259/pkgs/by-name/pa/pangolin-cli/package.nix#L32-L35

Is there a benefit to defining this completion so explicitly? I can see this being necessary if using something like carapace, but we're not using that currently, so I don't see the benefits myself.

I am open to using carapace as a library for this application, since it does provide completions for more esoteric shells such as nushell, elvish, and ion, and doesn't bloat binary size all that much.

[404Simon]

To my knowledge, the pangolin completion command already exists.

It is also being used in generation of completion scripts when building in the nixpkgs repository, as shown here: https://github.com/NixOS/nixpkgs/blob/3017d2b27b532d627c396a5351bee1c9d0e8b259/pkgs/by-name/pa/pangolin-cli/package.nix#L32-L35

Is there a benefit to defining this completion so explicitly? I can see this being necessary if using something like carapace, but we're not using that currently, so I don't see the benefits myself.

I am open to using carapace as a library for this application, since it does provide completions for more esoteric shells such as nushell, elvish, and ion, and doesn't bloat binary size all that much.

My mistake here. I didn’t actually try the existing completion and only checked pangolin --help, which doesn’t show the command. I will close this PR.

[water-sucks]

My mistake here. I didn’t actually try the existing completion and only checked pangolin --help, which doesn’t show the command. I will close this PR.

No worries! The completion command is hidden by default. This is because the completion scripts should ideally be distributed alongside Pangolin's CLI itself anyway by system package maintainers (similar to the example from nixpkgs that I linked prior) or created by the installer.