Add support for fig completions (#5669)

## Description

This fixes #5474

This is the first part of #5612, which will be split into several
smaller PRs


## Checklist

- [x] I have linked to any relevant issues.
- [x] I have commented my code, particularly in hard-to-understand
areas.
- [x] I have updated the documentation where relevant (API docs, the
reference, and the Sway book).
- [x] I have added tests that prove my fix is effective or that my
feature works.
- [x] I have added (or requested a maintainer to add) the necessary
`Breaking*` or `New Feature` labels where relevant.
- [x] I have done my best to ensure that my PR adheres to [the Fuel Labs
Code Review
Standards](https://github.com/FuelLabs/rfcs/blob/master/text/code-standards/external-contributors.md).
- [x] I have requested a review from the relevant team or maintainers.

forc-plugins/forc-crypto/src/keys/new_key.rs

@@ -11,8 +11,6 @@ use libp2p_identity::{secp256k1, Keypair, PeerId};
 use serde_json::json;
 use std::ops::Deref;
 
-const ABOUT: &str = "Creates a new key for use with fuel-core";
-
 forc_util::cli_examples! {
     crate::Command {
         [ Creates a new key default for block production => "forc crypto new-key" ]
@@ -21,9 +19,9 @@ forc_util::cli_examples! {
     }
 }
 
-/// Generate a random new secret & public key in the format expected by fuel-core
+/// Creates a new key for use with fuel-core
 #[derive(Debug, clap::Args)]
-#[clap(version, about = ABOUT, after_help = help())]
+#[clap(version, after_help = help())]
 pub struct Arg {
     /// Key type to generate. It can either be `block-production` or `peering`.
     #[clap(

forc-plugins/forc-crypto/src/keys/parse_secret.rs

@@ -5,20 +5,17 @@ use libp2p_identity::{secp256k1, Keypair, PeerId};
 use serde_json::json;
 use std::{ops::Deref, str::FromStr};
 
-const ABOUT: &str = "Parses a private key to view the associated public key";
-
 forc_util::cli_examples! {
     crate::Command {
         [ Parses the secret of a block production  => "forc crypto parse-secret \"f5204427d0ab9a311266c96a377f7c329cb8a41b9088225b6fcf40eefb423e28\"" ]
         [ Parses the secret of a peering  => "forc crypto parse-secret -k peering \"f5204427d0ab9a311266c96a377f7c329cb8a41b9088225b6fcf40eefb423e28\"" ]
     }
 }
 
-/// Parse a secret key to view the associated public key
+/// Parses a private key to view the associated public key
 #[derive(Debug, clap::Args)]
 #[clap(
     version,
-    about = ABOUT,
     after_help = help(),
 )]
 pub struct Arg {

forc-plugins/forc-crypto/src/main.rs

@@ -16,8 +16,6 @@ mod keccak256;
 mod keys;
 mod sha256;
 
-const ABOUT: &str = "Forc plugin for hashing arbitrary data.";
-
 fn help() -> &'static str {
     Box::leak(
         format!(
@@ -32,10 +30,10 @@ fn help() -> &'static str {
     )
 }
 
+/// Forc plugin for hashing arbitrary data
 #[derive(Debug, Parser)]
 #[clap(
     name = "forc-crypto",
-    about = ABOUT,
     after_help = help(),
     version
 )]

forc-plugins/forc-doc/src/cli.rs

@@ -2,8 +2,6 @@
 use clap::Parser;
 use forc_pkg::source::IPFSNode;
 
-const ABOUT: &str = "Forc plugin for building a Sway package's documentation";
-
 forc_util::cli_examples! {
     crate::Command {
         [ Build the docs for a project in the current path => "forc doc"]
@@ -14,10 +12,10 @@ forc_util::cli_examples! {
     }
 }
 
+/// Forc plugin for building a Sway package's documentation
 #[derive(Debug, Parser, Default)]
 #[clap(
     name = "forc-doc",
-    about = ABOUT,
     after_help = help(),
     version
 )]

forc-plugins/forc-fmt/src/main.rs

@@ -36,7 +36,7 @@ forc_util::cli_examples! {
 #[derive(Debug, Parser)]
 #[clap(
     name = "forc-fmt",
-    about = "Forc plugin for running the Sway code formatter.",
+    about = "Forc plugin for running the Sway code formatter",
     after_help = help(),
     version
 )]

forc-plugins/forc-lsp/src/main.rs

@@ -11,7 +11,7 @@ use clap::Parser;
 #[derive(Debug, Parser)]
 #[clap(
     name = "forc-lsp",
-    about = "Forc plugin for the Sway LSP (Language Server Protocol) implementation.",
+    about = "Forc plugin for the Sway LSP (Language Server Protocol) implementation",
     version
 )]
 struct App {}

forc/Cargo.toml

@@ -22,6 +22,7 @@ ansi_term = "0.12"
 anyhow = "1.0.41"
 clap = { version = "3.1", features = ["cargo", "derive", "env"] }
 clap_complete = "3.1"
+clap_complete_fig = "3.1"
 forc-pkg = { version = "0.52.1", path = "../forc-pkg" }
 forc-test = { version = "0.52.1", path = "../forc-test" }
 forc-tracing = { version = "0.52.1", path = "../forc-tracing" }
@@ -50,3 +51,6 @@ default = []
 test = []
 util = []
 uwu = ["uwuify"]
+
+[dev-dependencies]
+completest-pty = "0.5.0"