feat: Add Fields impl for Link (#542)

## Closes

-  #501 
## Description
Add implementation of `Field` trait for `Link`.

## Checklist

Delete any checklist items that do not apply (e.g. if your change is
minor, it may not require documentation updates).

- [x] Unit tests
- [ ] Documentation, including doctests
- [x] Git history is linear
- [x] Commit messages are descriptive
- [x] (optional) Git commit messages follow [conventional
commits](https://www.conventionalcommits.org/en/v1.0.0/)
- [x] Code is formatted (`cargo fmt`)
- [x] `cargo test`
- [x] Changes are added to the CHANGELOG

<!-- markdownlint-disable-file MD041 -->

---------

Co-authored-by: Pete Gadomski <pete.gadomski@gmail.com>

crates/core/CHANGELOG.md

@@ -6,6 +6,10 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 
 ## [Unreleased]
 
+### Added
+
+- `Fields` trait impl for `Link` ([#542](https://github.com/stac-utils/stac-rs/pull/542))
+
 ## [0.11.0] - 2024-11-12
 
 ### Added

crates/types/Cargo.toml

@@ -21,6 +21,7 @@ serde_json.workspace = true
 thiserror.workspace = true
 url = { workspace = true, features = ["serde"] }
 tracing.workspace = true
+stac-derive.workspace = true
 
 [dev-dependencies]
 assert-json-diff.workspace = true

crates/types/src/lib.rs

@@ -19,3 +19,4 @@ pub use {
 
 /// The default STAC version of this library.
 pub const STAC_VERSION: Version = Version::v1_1_0;
+extern crate self as stac_types;

crates/types/src/link.rs

@@ -4,6 +4,7 @@ use crate::{mime::APPLICATION_GEOJSON, Error, Href, Result, SelfHref};
 use mime::APPLICATION_JSON;
 use serde::{Deserialize, Serialize};
 use serde_json::{Map, Value};
+use stac_derive::Fields;
 
 /// Child links.
 pub const CHILD_REL: &str = "child";
@@ -31,7 +32,7 @@ pub const COLLECTION_REL: &str = "collection";
 /// Generally we keep STAC API structures in the [stac-api
 /// crate](https://github.com/stac-utils/stac-rs/stac-api), but in this case it
 /// was simpler to include these attributes in the base [Link] rather to create a new one.
-#[derive(Debug, Serialize, Deserialize, PartialEq, Clone)]
+#[derive(Debug, Serialize, Deserialize, PartialEq, Clone, Fields)]
 pub struct Link {
     /// The actual link in the format of an URL.
     ///