Initial commit: RR3 Community Server with web admin panel

- ASP.NET Core 8 REST API server
- 12 API endpoints matching EA Synergy protocol
- SQLite database with Entity Framework Core
- Web admin panel with Bootstrap 5
- User, Catalog, Session, Purchase management
- Comprehensive documentation

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

RR3CommunityServer/Controllers/DrmController.cs

@@ -0,0 +1,76 @@
+using Microsoft.AspNetCore.Mvc;
+using RR3CommunityServer.Models;
+using RR3CommunityServer.Services;
+
+namespace RR3CommunityServer.Controllers;
+
+[ApiController]
+[Route("drm/api")]
+public class DrmController : ControllerBase
+{
+    private readonly IDrmService _drmService;
+    private readonly ILogger<DrmController> _logger;
+
+    public DrmController(IDrmService drmService, ILogger<DrmController> logger)
+    {
+        _drmService = drmService;
+        _logger = logger;
+    }
+
+    [HttpGet("core/getNonce")]
+    public async Task<ActionResult<SynergyResponse<DrmNonceResponse>>> GetNonce()
+    {
+        _logger.LogInformation("GetNonce request");
+
+        var nonce = await _drmService.GenerateNonce();
+
+        var response = new SynergyResponse<DrmNonceResponse>
+        {
+            resultCode = 0,
+            message = "Success",
+            data = new DrmNonceResponse
+            {
+                nonce = nonce,
+                expiresAt = DateTimeOffset.UtcNow.AddMinutes(5).ToUnixTimeSeconds()
+            }
+        };
+
+        return Ok(response);
+    }
+
+    [HttpGet("core/getPurchasedItems")]
+    public async Task<ActionResult<SynergyResponse<List<PurchasedItem>>>> GetPurchasedItems()
+    {
+        var synergyId = HttpContext.Items["EAM-USER-ID"]?.ToString() ?? "default";
+        _logger.LogInformation("GetPurchasedItems for user: {SynergyId}", synergyId);
+
+        var purchases = await _drmService.GetPurchasedItems(synergyId);
+
+        var response = new SynergyResponse<List<PurchasedItem>>
+        {
+            resultCode = 0,
+            message = "Success",
+            data = purchases
+        };
+
+        return Ok(response);
+    }
+
+    [HttpPost("android/verifyAndRecordPurchase")]
+    public async Task<ActionResult<SynergyResponse<object>>> VerifyPurchase([FromBody] PurchaseVerificationRequest request)
+    {
+        var synergyId = HttpContext.Items["EAM-USER-ID"]?.ToString() ?? "default";
+        _logger.LogInformation("VerifyAndRecordPurchase: user={User}, sku={Sku}", synergyId, request.sku);
+
+        var verified = await _drmService.VerifyAndRecordPurchase(synergyId, request);
+
+        var response = new SynergyResponse<object>
+        {
+            resultCode = verified ? 0 : -1,
+            message = verified ? "Purchase verified" : "Purchase verification failed",
+            data = new { verified = verified }
+        };
+
+        return Ok(response);
+    }
+}