refactor(cli): embed banner.txt content as CLI long_about description

src/banner.txt

@@ -5,3 +5,5 @@
 ▀  ▐▌ ▐▌    
     ▝▀▜▌    
    ▐▙▄▞▘    
+
+Project-scoped PostgreSQL instance manager

src/cli.rs

@@ -8,7 +8,7 @@ const STYLES: styling::Styles = styling::Styles::styled()
 
 #[derive(Parser)]
 #[command(name = "pgd")]
-#[command(about = "Project-scoped PostgreSQL instance manager", long_about = None)]
+#[command(about = "Project-scoped PostgreSQL instance manager", long_about = include_str!("./banner.txt"))]
 #[command(version)]
 #[command(styles = STYLES)]
 pub struct Cli {

src/main.rs

@@ -18,8 +18,6 @@ use crate::{
 
 #[tokio::main]
 async fn main() -> Result<()> {
-    println!("{}", include_str!("./banner.txt"));
-
     let cli = Cli::parse();
     init_tracing(cli.verbose);