Implement Display instead ToString for Container State as per clippy …

…warning

src/docker/manager.rs

@@ -14,6 +14,7 @@ use crate::{
     utils::run_command,
 };
 use serde::{Deserialize, Serialize};
+use std::fmt;
 use std::fs::File;
 use std::io::Write;
 use std::{
@@ -195,7 +196,7 @@ impl DockerManager {
 
         if let Some(state) = filter {
             cmd.push("--filter".to_string());
-            cmd.push(format!("status={}", state.to_string()));
+            cmd.push(format!("status={}", state));
         }
 
         // Convert Vec<String> to Vec<&str> for compatibility with run_docker_compose
@@ -374,17 +375,18 @@ impl DockerManager {
     }
 }
 
-impl ToString for ContainerState {
-    fn to_string(&self) -> String {
-        match self {
-            ContainerState::Created => "created".into(),
-            ContainerState::Exited => "exited".into(),
-            ContainerState::Running => "running".into(),
-            ContainerState::Paused => "paused".into(),
-            ContainerState::Restarting => "restarting".into(),
-            ContainerState::Removing => "removing".into(),
-            ContainerState::Dead => "dead".into(),
-            ContainerState::Unknown => "unknown".into(),
-        }
+impl fmt::Display for ContainerState {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        let state_str = match self {
+            ContainerState::Created => "created",
+            ContainerState::Exited => "exited",
+            ContainerState::Running => "running",
+            ContainerState::Paused => "paused",
+            ContainerState::Restarting => "restarting",
+            ContainerState::Removing => "removing",
+            ContainerState::Dead => "dead",
+            ContainerState::Unknown => "unknown",
+        };
+        write!(f, "{}", state_str)
     }
 }