Enforce ordering of commands/sub-commands according to source

By default, clap orders command alphabetically, which can be quite
    confusing when listing commands with `--help`:

    ```
    SUBCOMMANDS:
        eval      Evaluate an Untyped Plutus Core program
        flat      Encode textual Untyped Plutus Core to flat bytes
        fmt       Format an Untyped Plutus Core program
        help      Print this message or the help of the given subcommand(s)
        unflat    Decode flat bytes to textual Untyped Plutus Cor
    ```

    It is possible to instrument clap to order commands in the same way
    they are declared in the source, giving us back the freedom to order
    and group them in a manner that makes sense, e.g.:

    ```
    SUBCOMMANDS:
        fmt       Format an Untyped Plutus Core program
        eval      Evaluate an Untyped Plutus Core program
        flat      Encode textual Untyped Plutus Core to flat bytes
        unflat    Decode flat bytes to textual Untyped Plutus Cor
        help      Print this message or the help of the given subcommand(s)
    ```

crates/cli/src/cmd/tx/mod.rs

@@ -4,6 +4,7 @@ use clap::Subcommand;
 
 /// Commands for working with transactions
 #[derive(Subcommand)]
+#[clap(setting(clap::AppSettings::DeriveDisplayOrder))]
 pub enum Cmd {
     Simulate(simulate::Args),
 }

crates/cli/src/cmd/uplc/mod.rs

@@ -7,6 +7,7 @@ use clap::Subcommand;
 
 /// Commands for working with untyped Plutus-core
 #[derive(Subcommand)]
+#[clap(setting(clap::AppSettings::DeriveDisplayOrder))]
 pub enum Cmd {
     Fmt(fmt::Args),
     Eval(eval::Args),

crates/cli/src/main.rs

@@ -7,6 +7,7 @@ use cmd::{build, check, new, tx, uplc};
 #[derive(Parser)]
 #[clap(version, about, long_about = None)]
 #[clap(propagate_version = true)]
+#[clap(setting(clap::AppSettings::DeriveDisplayOrder))]
 pub enum Cmd {
     New(new::Args),
     Build(build::Args),
@@ -28,9 +29,9 @@ impl Default for Cmd {
 fn main() -> miette::Result<()> {
     miette::set_panic_hook();
     match Cmd::default() {
+        Cmd::New(args) => new::exec(args),
         Cmd::Build(args) => build::exec(args),
         Cmd::Check(args) => check::exec(args),
-        Cmd::New(args) => new::exec(args),
         Cmd::Tx(sub_cmd) => tx::exec(sub_cmd),
         Cmd::Uplc(sub_cmd) => uplc::exec(sub_cmd),
     }