Wire NowPlayingStats to live aggregates: add SQL track duration column, stats endpoint, and duration backfill

DeepDrftAPI/Controllers/StatsController.cs

@@ -0,0 +1,36 @@
+using DeepDrftData;
+using Microsoft.AspNetCore.Mvc;
+
+namespace DeepDrftAPI.Controllers;
+
+[ApiController]
+[Route("api/[controller]")]
+public class StatsController : ControllerBase
+{
+    private readonly ITrackService _sqlTrackService;
+    private readonly ILogger<StatsController> _logger;
+
+    public StatsController(ITrackService sqlTrackService, ILogger<StatsController> logger)
+    {
+        _sqlTrackService = sqlTrackService;
+        _logger = logger;
+    }
+
+    // GET api/stats/home (unauthenticated)
+    // Aggregate figures behind the public home hero stat row — one read for all three cards. Same auth
+    // posture as the other public browse reads (GET api/track/page). The aggregation lives in the SQL
+    // service/repository; this controller stays a thin HTTP boundary.
+    [HttpGet("home")]
+    public async Task<ActionResult> GetHome(CancellationToken ct = default)
+    {
+        var result = await _sqlTrackService.GetHomeStats(ct);
+        if (!result.Success || result.Value is null)
+        {
+            var error = result.Messages.FirstOrDefault()?.Message ?? "Unknown error";
+            _logger.LogError("GetHome stats failed: {Error}", error);
+            return StatusCode(500, "Failed to load stats");
+        }
+
+        return Ok(result.Value);
+    }
+}