refactor(peer): split bulk request dispatch

Move file-chunk and Stream Install branches into focused helpers so the new admission path remains within the workspace's strict Clippy limits without changing request behavior.

Test Plan:
- just clippy
- git diff --check

crates/lanspread-peer/src/services/server.rs

@@ -430,8 +430,7 @@ async fn run_server_body(
 
                     if !has_child_capacity(connection_tasks.len(), MAX_ESTABLISHED_CONNECTIONS) {
                         log::warn!(
-                            "Closing excess peer connection from {remote_addr} at application limit {}",
-                            MAX_ESTABLISHED_CONNECTIONS,
+                            "Closing excess peer connection from {remote_addr} at application limit {MAX_ESTABLISHED_CONNECTIONS}",
                         );
                         connection.close(application::Error::UNKNOWN);
                         continue;

crates/lanspread-peer/src/services/stream.rs

@@ -300,13 +300,43 @@ async fn dispatch_request(
                 .schedule_hint(StateDomain::CallToPlay, hint, source_ip);
             DispatchResult::close(framed_tx)
         }
-        Request::GetGameFileChunk {
+        request @ Request::GetGameFileChunk { .. } => {
+            dispatch_file_chunk(ctx, request, framed_tx, stream_shutdown).await
+        }
+        Request::StreamInstall {
+            game_id,
+            content_id,
+        } => {
+            dispatch_stream_install(
+                ctx,
+                game_id,
+                content_id,
+                framed_tx,
+                stream_shutdown,
+                admission,
+                origin,
+            )
+            .await
+        }
+    }
+}
+
+async fn dispatch_file_chunk(
+    ctx: &PeerCtx,
+    request: Request,
+    framed_tx: ResponseWriter,
+    stream_shutdown: &CancellationToken,
+) -> DispatchResult {
+    let Request::GetGameFileChunk {
         game_id,
         content_id,
         relative_path,
         offset,
         length,
-        } => {
+    } = request
+    else {
+        unreachable!("file-chunk dispatcher received a different request")
+    };
     match handle_file_chunk_request(
         ctx,
         game_id,
@@ -323,12 +353,17 @@ async fn dispatch_request(
         ChunkDispatch::Reset(writer) => DispatchResult::reset(writer),
     }
 }
-        Request::StreamInstall {
-            game_id,
-            content_id,
-        } => {
-            let Some(mut stream_install_admission) = admission.try_acquire_stream_install(origin)
-            else {
+
+async fn dispatch_stream_install(
+    ctx: &PeerCtx,
+    game_id: String,
+    content_id: lanspread_db::content_manifest::ContentId,
+    framed_tx: ResponseWriter,
+    stream_shutdown: &CancellationToken,
+    admission: &ServerAdmission,
+    origin: ObservedOrigin,
+) -> DispatchResult {
+    let Some(mut stream_install_admission) = admission.try_acquire_stream_install(origin) else {
         let mut tx = framed_tx.into_inner();
         let _ = tx.reset(application::Error::UNKNOWN);
         return DispatchResult::reset(FramedWrite::new(tx, control_codec()));
@@ -346,8 +381,6 @@ async fn dispatch_request(
     drop(stream_install_admission);
     DispatchResult::close(writer)
 }
-    }
-}
 
 fn reset_response_writer(framed_tx: ResponseWriter, label: &str) -> DispatchResult {
     let mut tx = framed_tx.into_inner();