refactor: improve RemoteAction naming consistency

- CloudInitValidator: 'cloud-init-completion' → 'cloud-init-validation'
- DockerValidator: 'docker-installation' → 'docker-validation'
- DockerComposeValidator: 'docker-compose-installation' → 'docker-compose-validation'

All action names now follow consistent '-validation' suffix pattern and
better describe their primary purpose of validating server state.

Author: josecelano

src/actions/cloud_init.rs

@@ -26,7 +26,7 @@ impl CloudInitValidator {
 
 impl RemoteAction for CloudInitValidator {
     fn name(&self) -> &'static str {
-        "cloud-init-completion"
+        "cloud-init-validation"
     }
 
     async fn execute(&self, server_ip: &str) -> Result<()> {

src/actions/docker.rs

@@ -26,7 +26,7 @@ impl DockerValidator {
 
 impl RemoteAction for DockerValidator {
     fn name(&self) -> &'static str {
-        "docker-installation"
+        "docker-validation"
     }
 
     async fn execute(&self, server_ip: &str) -> Result<()> {

src/actions/docker_compose.rs

@@ -26,7 +26,7 @@ impl DockerComposeValidator {
 
 impl RemoteAction for DockerComposeValidator {
     fn name(&self) -> &'static str {
-        "docker-compose-installation"
+        "docker-compose-validation"
     }
 
     async fn execute(&self, server_ip: &str) -> Result<()> {