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

DeepDrftPublic.Client/Clients/StatsClient.cs

@@ -0,0 +1,39 @@
+using DeepDrftModels.DTOs;
+using NetBlocks.Models;
+using System.Text.Json;
+
+namespace DeepDrftPublic.Client.Clients;
+
+/// <summary>
+/// HTTP client for the public stats read surface. Uses the named <c>"DeepDrft.API"</c> client like
+/// <see cref="TrackClient"/> and <see cref="ReleaseClient"/>: on WASM it points at the public host and
+/// proxies through <c>StatsProxyController</c>; on SSR prerender it points directly at DeepDrftAPI. The
+/// route is an unauthenticated read; the response deserializes as a bare DTO (no ApiResultDto envelope),
+/// matching the API's <c>Ok(value)</c> shape.
+/// </summary>
+public class StatsClient
+{
+    private static readonly JsonSerializerOptions JsonOptions = new() { PropertyNameCaseInsensitive = true };
+
+    private readonly HttpClient _http;
+
+    public StatsClient(IHttpClientFactory httpClientFactory)
+    {
+        _http = httpClientFactory.CreateClient("DeepDrft.API");
+    }
+
+    public async Task<ApiResult<HomeStatsDto>> GetHomeStats()
+    {
+        var response = await _http.GetAsync("api/stats/home");
+
+        if (!response.IsSuccessStatusCode)
+            return ApiResult<HomeStatsDto>.CreateFailResult($"HTTP {(int)response.StatusCode}");
+
+        var json = await response.Content.ReadAsStringAsync();
+        var stats = JsonSerializer.Deserialize<HomeStatsDto>(json, JsonOptions);
+
+        return stats is not null
+            ? ApiResult<HomeStatsDto>.CreatePassResult(stats)
+            : ApiResult<HomeStatsDto>.CreateFailResult("Failed to deserialize response");
+    }
+}