feat: add serde derive to Score types

This commit adds `serde` dependency and derives `Serialize` trait for `Score` types. This is necessary for serialization and deserialization of these types, which is required to display Scores to various user interfaces

- Added `serde` dependency to `harmony_types/Cargo.toml`.
- Added `serde::Serialize` derive macro to `MacAddress` in `harmony_types/src/lib.rs`.
- Added `serde::Serialize` derive macro to `Config` in `opnsense-config/src/config/config.rs`.
- Added `serde::Serialize` derive macro to `Score` in `harmony_types/src/lib.rs`.
- Added `serde::Serialize` derive macro to `Config` and `Score` in relevant modules.
- Added placeholder `todo!()` implementations for `serialize` methods. These will be implemented in future commits.

harmony/src/domain/topology/mod.rs

@@ -12,6 +12,7 @@ mod network;
 pub use host_binding::*;
 pub use http::*;
 pub use network::*;
+use serde::Serialize;
 pub use tftp::*;
 
 use std::net::IpAddr;
@@ -20,8 +21,6 @@ pub trait Topology {
     fn name(&self) -> &str;
 }
 
-pub trait Capability {}
-
 pub type IpAddress = IpAddr;
 
 #[derive(Debug, Clone)]
@@ -30,6 +29,18 @@ pub enum Url {
     Url(url::Url),
 }
 
+impl Serialize for Url {
+    fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
+    where
+        S: serde::Serializer,
+    {
+        match self {
+            Url::LocalFolder(path) => serializer.serialize_str(path),
+            Url::Url(url) => serializer.serialize_str(&url.as_str()),
+        }
+    }
+}
+
 impl std::fmt::Display for Url {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
         match self {
@@ -48,7 +59,7 @@ impl std::fmt::Display for Url {
 /// - A control plane node
 ///
 /// This abstraction focuses on the logical role and services, independent of the physical hardware.
-#[derive(Debug, Clone)]
+#[derive(Debug, Clone, Serialize)]
 pub struct LogicalHost {
     /// The IP address of this logical host.
     pub ip: IpAddress,
@@ -130,3 +141,23 @@ fn increment_ip(ip: IpAddress, increment: u32) -> Option<IpAddress> {
         }
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use serde_json;
+
+    #[test]
+    fn test_serialize_local_folder() {
+        let url = Url::LocalFolder("path/to/folder".to_string());
+        let serialized = serde_json::to_string(&url).unwrap();
+        assert_eq!(serialized, "\"path/to/folder\"");
+    }
+
+    #[test]
+    fn test_serialize_url() {
+        let url = Url::Url(url::Url::parse("https://example.com").unwrap());
+        let serialized = serde_json::to_string(&url).unwrap();
+        assert_eq!(serialized, "\"https://example.com/\"");
+    }
+}