feat: Split subcommand main modules from main

src/commands.rs

@@ -0,0 +1 @@
+pub mod version;

src/commands/version.rs

@@ -0,0 +1,4 @@
+pub fn run() {
+    let version = super::super::VERSION;
+    println!("Running gazer v{version}");
+}

src/main.rs

@@ -1,4 +1,5 @@
 // Entry point.
+mod commands;
 use clap::{Parser, Subcommand};
 
 const VERSION: &'static str = "0.0.0";
@@ -20,7 +21,7 @@ fn main() {
     let cli = Cli::parse();
     match &cli.command {
         Some(Commands::Version {}) => {
-            println!("Running gazer v{VERSION}");
+            commands::version::run();
         }
         None => {}
     }