Add concurrency handling implementation with ticket management and file locking

cpp/src/Public/sweepstore/concurrency.h

@@ -0,0 +1,30 @@
+#pragma once
+
+#include <cstdint>
+#include <functional>
+#include <iosfwd>
+#include <thread>
+
+#define STALE_HEARTBEAT_THRESHOLD_MS 5000
+
+enum SweepstoreTicketOperation : int;
+
+namespace SweepstoreConcurrency {
+
+    void spawnTicket(std::string filePath,
+        const SweepstoreTicketOperation& operation,
+        const uint32_t keyHash,
+        const uint32_t targetSize,
+        const std::function<void()> onApproved,
+        std::string debugLabel = ""
+    );
+
+    void initialiseMaster(std::string filePath);
+
+    inline void initialiseMasterAsync(std::string filePath) {
+        std::thread([&filePath]() {
+            initialiseMaster(filePath);
+        }).detach();
+    }
+
+}