Add log-only account sync save hooks

src/AccountSync.hh

@@ -0,0 +1,38 @@
+#pragma once
+
+#include <cstddef>
+#include <cstdint>
+#include <cstdio>
+#include <string>
+
+namespace AccountSync {
+
+inline void notify_account_saved(uint32_t account_id, const std::string& filename) {
+  std::fprintf(stderr,
+      "[AccountSync] event=account_saved account_id=%010u filename=%s\n",
+      static_cast<unsigned int>(account_id),
+      filename.c_str());
+}
+
+inline void notify_backup_saved(uint32_t account_id, size_t slot, const std::string& filename) {
+  std::fprintf(stderr,
+      "[AccountSync] event=backup_saved account_id=%010u slot=%zu filename=%s\n",
+      static_cast<unsigned int>(account_id),
+      slot,
+      filename.c_str());
+}
+
+inline void notify_player_state_saved(
+    const char* reason,
+    uint32_t account_id,
+    const std::string& bb_username,
+    const std::string& filename) {
+  std::fprintf(stderr,
+      "[AccountSync] event=player_state_saved reason=%s account_id=%010u bb_username=%s filename=%s\n",
+      reason,
+      static_cast<unsigned int>(account_id),
+      bb_username.c_str(),
+      filename.c_str());
+}
+
+} // namespace AccountSync