refactor(knot): make `model::RepositoryManager` dyn-compatible

Re-write `can_push()` method as a boxed future.

Signed-off-by: tjh <did:plc:65gha4t3avpfpzmvpbwovss7>

crates/knot/src/model.rs

···
     http::request::Parts,
 };
 use errors::RepoNotFound;
+use futures_util::{FutureExt, future::BoxFuture};
 use gix::{Repository, open::Options};
 use identity::Resolver;
 use jetstream::JetstreamClient;
···
 
     /// Determine whether the specified account has permission to push to the
     /// specified repository.
-    fn can_push(&self, repo: &RepoPath, did: &Did) -> impl Future<Output = bool>;
+    fn can_push(&self, repo: &RepoPath, did: &Did) -> BoxFuture<'_, bool>;
 }
 
 impl RepositoryManager for Knot {
···
     }
 
     // Currently defers to the real knotserver's internal "/push-allowed" route.
-    async fn can_push(&self, repo: &RepoPath, did: &Did) -> bool {
+    fn can_push(&self, repo: &RepoPath, did: &Did) -> BoxFuture<'_, bool> {
         use reqwest::StatusCode;
 
-        let url = format!("http://localhost:5444/push-allowed?user={did}&repo={repo}");
-        self.private_http()
-            .get(url)
-            .send()
-            .await
-            .inspect_err(|err| tracing::error!(?err, "failed to query push permission"))
-            .map(|response| response.status() == StatusCode::NO_CONTENT)
-            .unwrap_or_default()
+        let request = self
+            .private_http()
+            .get(format!(
+                "http://localhost:5444/push-allowed?user={did}&repo={repo}"
+            ))
+            .send();
+
+        async move {
+            request
+                .await
+                .inspect_err(|error| tracing::error!(?error, "failed to query push permission"))
+                .map(|response| response.status() == StatusCode::NO_CONTENT)
+                .unwrap_or_default()
+        }
+        .boxed()
     }
 }