move data stores into their own folders like the go project

dotnet/SafelyYou/Data/UploadTimes.cs

@@ -0,0 +1,29 @@
+using System.Collections.Concurrent;
+using System.Numerics;
+
+namespace SafelyYou.Data;
+
+public sealed class UploadTimes
+{
+    private readonly Lock _lock = new();
+    private readonly ConcurrentDictionary<DeviceId, (BigInteger TotalUploadTime, int UploadCounts)> _uploadHistories = new();
+
+    public void Add(DeviceId deviceId, BigInteger uploadTimeNanos)
+    {
+        lock (_lock)
+        {
+            if (!_uploadHistories.TryGetValue(deviceId, out var history))
+            {
+                history = (BigInteger.Zero, 0);
+            }
+
+            _uploadHistories[deviceId] = (history.TotalUploadTime + uploadTimeNanos, history.UploadCounts + 1);
+        }
+    }
+
+    public BigInteger AverageUploadTimeNanoseconds(DeviceId deviceId)
+    {
+        if (!_uploadHistories.TryGetValue(deviceId, out var history)) return BigInteger.Zero;
+        return history.TotalUploadTime / history.UploadCounts;
+    }
+}