fix(opnsense-config): ensure load balancer service configuration is idempotent (#129)

The previous implementation blindly added HAProxy components without checking for existing configurations on the same port, which caused duplicate entries and errors when a service was updated.

This commit refactors the logic to a robust "remove-then-add" strategy. The configure_service method now finds and removes any existing frontend and its dependent components (backend, servers, health check) before adding the new, complete service definition.

This change makes the process fully idempotent, preventing configuration drift and ensuring a predictable state.

Co-authored-by: Ian Letourneau <letourneau.ian@gmail.com>
Reviewed-on: #129

opnsense-config-xml/src/data/haproxy.rs

@@ -77,7 +77,7 @@ impl YaSerializeTrait for HAProxyId {
     }
 }
 
-#[derive(PartialEq, Debug)]
+#[derive(PartialEq, Debug, Clone)]
 pub struct HAProxyId(String);
 
 impl Default for HAProxyId {
@@ -297,7 +297,7 @@ pub struct HAProxyFrontends {
     pub frontend: Vec<Frontend>,
 }
 
-#[derive(Default, PartialEq, Debug, YaSerialize, YaDeserialize)]
+#[derive(Clone, Default, PartialEq, Debug, YaSerialize, YaDeserialize)]
 pub struct Frontend {
     #[yaserde(attribute = true)]
     pub uuid: String,
@@ -310,7 +310,7 @@ pub struct Frontend {
     pub bind_options: MaybeString,
     pub mode: String,
     #[yaserde(rename = "defaultBackend")]
-    pub default_backend: String,
+    pub default_backend: Option<String>,
     pub ssl_enabled: i32,
     pub ssl_certificates: MaybeString,
     pub ssl_default_certificate: MaybeString,
@@ -416,7 +416,7 @@ pub struct HAProxyBackends {
     pub backends: Vec<HAProxyBackend>,
 }
 
-#[derive(Default, PartialEq, Debug, YaSerialize, YaDeserialize)]
+#[derive(Clone, Default, PartialEq, Debug, YaSerialize, YaDeserialize)]
 pub struct HAProxyBackend {
     #[yaserde(attribute = true, rename = "uuid")]
     pub uuid: String,
@@ -535,7 +535,7 @@ pub struct HAProxyServers {
     pub servers: Vec<HAProxyServer>,
 }
 
-#[derive(Default, PartialEq, Debug, YaSerialize, YaDeserialize)]
+#[derive(Clone, Default, PartialEq, Debug, YaSerialize, YaDeserialize)]
 pub struct HAProxyServer {
     #[yaserde(attribute = true, rename = "uuid")]
     pub uuid: String,
@@ -543,8 +543,8 @@ pub struct HAProxyServer {
     pub enabled: u8,
     pub name: String,
     pub description: MaybeString,
-    pub address: String,
-    pub port: u16,
+    pub address: Option<String>,
+    pub port: Option<u16>,
     pub checkport: MaybeString,
     pub mode: String,
     pub multiplexer_protocol: MaybeString,
@@ -589,7 +589,7 @@ pub struct HAProxyHealthChecks {
     pub healthchecks: Vec<HAProxyHealthCheck>,
 }
 
-#[derive(Default, PartialEq, Debug, YaSerialize, YaDeserialize)]
+#[derive(Clone, Default, PartialEq, Debug, YaSerialize, YaDeserialize)]
 pub struct HAProxyHealthCheck {
     #[yaserde(attribute = true)]
     pub uuid: String,