CUB-10: Create IMoonrakerClient interface and DTOs

- Expanded IMoonrakerClient interface with 6 strongly-typed methods:
  - GetServerInfoAsync (Moonraker /server/info)
  - IsReachableAsync (connectivity check)
  - GetPrinterInfoAsync (Moonraker /printer/info)
  - GetPrintHistoryAsync (Moonraker /server/history/items)
  - GetPrintStatsAsync (Moonraker /printer/objects/query?print_stats)
  - GetDisplayStatusAsync (Moonraker /printer/objects/query?display_status)
  - GetFilamentUsageAsync (retained for backward compatibility)

- Created Domain/DTOs/Moonraker/ with 7 DTOs:
  - MoonrakerServerInfo, MoonrakerPrinterInfo, MoonrakerPrintJob
  - MoonrakerHistoryResponse, MoonrakerPrintStats
  - MoonrakerDisplayStatus, MoonrakerRequest

- Updated MoonrakerClient implementation to support all new methods
  with proper JSON parsing and mapping helpers

- Full XML doc comments on all public members

backend/Domain/DTOs/Moonraker/MoonrakerHistoryResponse.cs

@@ -0,0 +1,20 @@
+namespace Extrudex.Domain.DTOs.Moonraker;
+
+/// <summary>
+/// Response DTO for the Moonraker /server/history/items endpoint.
+/// Wraps the paginated list of print job history items.
+/// </summary>
+public class MoonrakerHistoryResponse
+{
+    /// <summary>
+    /// The list of print job history items returned by Moonraker.
+    /// Most recent jobs appear first (descending by start time).
+    /// </summary>
+    public List<MoonrakerPrintJob> Items { get; set; } = [];
+
+    /// <summary>
+    /// Total number of print jobs available on the server
+    /// (for pagination; the Items list may be a subset).
+    /// </summary>
+    public int TotalCount { get; set; }
+}