test(delete): differential + timing regression tests for per-directory delete plans

- Compare --delete-during/--delete-delay final state against rsync 3.4.1.
- Force a mid-transfer failure through a byte-slicing proxy: --delete-during has
  removed the processed directory's extra, --delete-delay has not.
- Create a destination entry while the transfer is in flight: it survives
  --delete-delay's snapshot but is removed by --delete-after's fresh end scan.
- Cover the --delete-delay type-conflict case now matching rsync.

src/client/client_send.c

@@ -1189,7 +1189,8 @@ static int send_chunk_delete_plans(Client* client, DeletePlanSender* plans, cons
     File* f = chunk->items[i];
     if (!f)
       continue;
-    if (delete_plan_send_for_path(client->file_descriptor, plans, file_wire_path(f), f->is_dir) != 0)
+    if (delete_plan_send_for_path(client->file_descriptor, plans, file_wire_path(f), f->is_dir) !=
+        0)
       return -1;
   }
   return 0;

src/server/receiver.c

@@ -259,8 +259,7 @@ int receiver_process(Config* config, int file_descriptor, const ReceiverSink* si
    the whole transfer succeeded.  See receiver_process_pending() for how the -m
    receiver defers that commit until its disk writer has drained. */
 int receiver_process_pending(Config* config, int file_descriptor, const ReceiverSink* sink,
-                             DeleteManifest** pending_manifest,
-                             DeletePlanSession** pending_plans) {
+                             DeleteManifest** pending_manifest, DeletePlanSession** pending_plans) {
   Status status;
   if (!receive_status(file_descriptor, &status))
     return -1;

src/server/receiver_pipeline.c

@@ -167,8 +167,8 @@ int receive_thread(void* pipeline_context) {
 
   ReceiverSink sink = {
       receiver_enqueue_file, context, false, false, NULL, receiver_pipeline_note_delete_limit};
-  if (receiver_process_pending((Config*)config, file_descriptor, &sink,
-                               &context->deferred_manifest, &context->deferred_plans) != 0) {
+  if (receiver_process_pending((Config*)config, file_descriptor, &sink, &context->deferred_manifest,
+                               &context->deferred_plans) != 0) {
     receiver_thread_fail(context);
     protocol_session_unbind();
     return thrd_error;

src/server/server.c

@@ -966,8 +966,7 @@ void handler(int file_descriptor) {
          arrived; with the disk writer drained, commit the deferred removals.
          --delete-during already applied its plans on the receive thread. */
       if (context->deferred_plans) {
-        DeleteCommitResult deletion =
-            delete_plan_session_commit(context->deferred_plans, config);
+        DeleteCommitResult deletion = delete_plan_session_commit(context->deferred_plans, config);
         if (deletion == DELETE_COMMIT_ERROR) {
           transfer_ok = false;
         } else if (deletion == DELETE_COMMIT_LIMIT_REACHED) {

src/shared/delete_plan.c

@@ -484,7 +484,8 @@ typedef struct PlanSkips {
   int count;
 } PlanSkips;
 
-static bool build_plan_skips(const Config* config, const DeletePlanSession* session, PlanSkips* out) {
+static bool build_plan_skips(const Config* config, const DeletePlanSession* session,
+                             PlanSkips* out) {
   out->entries = NULL;
   out->count = 0;
   int count = (config->delay_updates ? 1 : 0) + config->basis_count +
@@ -569,8 +570,8 @@ static bool process_extra_dir(int dirfd, const char* name, const char* child_rel
     return false;
   }
   bool survives = false;
-  bool ok = process_children(childfd, child_rel, NULL, NULL, false, force_now, skips, session,
-                             &survives);
+  bool ok =
+      process_children(childfd, child_rel, NULL, NULL, false, force_now, skips, session, &survives);
   close(childfd);
   if (!ok)
     return false;
@@ -637,8 +638,8 @@ static bool process_children(int dirfd, const char* dir_rel, const ArrayList* ke
   while ((entry = readdir(dir)) != NULL) {
     if (strcmp(entry->d_name, ".") == 0 || strcmp(entry->d_name, "..") == 0)
       continue;
-    char* child_rel = (strcmp(dir_rel, ".") == 0) ? str_dup(entry->d_name)
-                                                  : path_cat(dir_rel, entry->d_name);
+    char* child_rel =
+        (strcmp(dir_rel, ".") == 0) ? str_dup(entry->d_name) : path_cat(dir_rel, entry->d_name);
     if (!child_rel) {
       operation_ok = false;
       continue;
@@ -704,8 +705,8 @@ static bool apply_plan_dir(DeletePlanSession* session, const Config* config, con
     return false;
   }
   bool survives = false;
-  bool ok = process_children(dirfd, dir, dirs, files, strcmp(dir, ".") == 0, false, &skips,
-                             session, &survives);
+  bool ok = process_children(dirfd, dir, dirs, files, strcmp(dir, ".") == 0, false, &skips, session,
+                             &survives);
   free(skips.entries);
   close(dirfd);
   if (!ok)
@@ -719,8 +720,8 @@ static bool apply_missing(DeletePlanSession* session, const Config* config) {
   session->missing_applied = true;
   if (session->missing->size == 0)
     return true;
-  DeleteManifest manifest = {.keeps = NULL, .protected = NULL, .missing = session->missing,
-                             .dirs = NULL};
+  DeleteManifest manifest = {
+      .keeps = NULL, .protected = NULL, .missing = session->missing, .dirs = NULL};
   size_t remaining = budget_available(session) ? session->max_delete - session->deleted : 0;
   size_t deleted = 0;
   size_t skipped = 0;