feat: implement GetUsername for Forgejo adapter

src/auth/adapter/out/forge/forgejo/get_username.rs

@@ -0,0 +1,35 @@
+use serde::{Deserialize, Serialize};
+
+use super::Forgejo;
+use crate::auth::application::port::out::forge::{
+    errors::OutForgePortResult, get_username::GetUsername,
+};
+use crate::auth::domain::OAuthAccessToken;
+
+#[derive(Clone, Debug, Eq, PartialEq, PartialOrd, Ord, Serialize, Deserialize)]
+struct ForgejoUserResponse {
+    login: String,
+}
+
+#[async_trait::async_trait]
+impl GetUsername for Forgejo {
+    async fn get_username(&self, access_token: &OAuthAccessToken) -> OutForgePortResult<String> {
+        let u = {
+            let mut u = self.url().to_owned();
+            u.set_path("/api/v1/user");
+            u
+        };
+        let res = self
+            .http_client
+            .get(u)
+            .header(
+                reqwest::header::AUTHORIZATION,
+                format!("token {}", access_token.access_token),
+            )
+            .send()
+            .await
+            .unwrap();
+        let res: ForgejoUserResponse = res.json().await.unwrap();
+        Ok(res.login)
+    }
+}