raise upload size cap to ~1.86 GB and nginx timeouts to 1200s

Raise RequestSizeLimit/MultipartBodyLengthLimit on upload+replace-audio,
MaxUploadBytes in BatchUpload/BatchEdit, and DefaultResponseTimeoutSeconds to
1200s. Add client_max_body_size 2000m and proxy_read/send_timeout 1200s to the
nginx manager/public confs.

DeepDrftManager/Components/Pages/Tracks/BatchEdit.razor

@@ -114,8 +114,8 @@
 </MudContainer>
 
 @code {
-    // 1 GB ceiling matches DeepDrftAPI's per-request limit on api/track/upload.
-    private const long MaxUploadBytes = 1_073_741_824L;
+    // ~1.86 GB ceiling matches DeepDrftAPI's per-request limit on api/track/upload.
+    private const long MaxUploadBytes = 2_000_000_000L;
 
     // Release-title addressing (Album-mode batch Edit): loads the whole release by title.
     [Parameter] public string AlbumName { get; set; } = string.Empty;

DeepDrftManager/Components/Pages/Tracks/BatchUpload.razor

@@ -108,9 +108,9 @@
 </MudContainer>
 
 @code {
-    // 1 GB ceiling matches DeepDrftAPI's per-request limit on api/track/upload; the
+    // ~1.86 GB ceiling matches DeepDrftAPI's per-request limit on api/track/upload; the
     // streaming path means the limit caps the request, not in-memory buffering.
-    private const long MaxUploadBytes = 1_073_741_824L;
+    private const long MaxUploadBytes = 2_000_000_000L;
 
     private List<BatchRowModel> _tracks = new();
     private int _selectedIndex = -1;

DeepDrftManager/Services/CmsTrackService.cs

@@ -28,11 +28,11 @@ public class CmsTrackService : ICmsTrackService
     private const int DefaultIdleTimeoutSeconds = 90;
 
     // Response-wait budget: once the request body is fully on the wire the server runs AudioProcessor
-    // decode → vault write → SQL persist. For a several-hundred-MB WAV this can take many minutes.
+    // decode → vault write → SQL persist. For a multi-GB WAV this can exceed 10 minutes.
     // The idle heartbeat goes silent after the last byte, so a separate, larger deadline governs the
     // response-wait phase so a fully-uploaded file is never killed mid-persist.
     // Operator-tunable via Upload:ResponseTimeoutSeconds.
-    private const int DefaultResponseTimeoutSeconds = 600; // 10 minutes
+    private const int DefaultResponseTimeoutSeconds = 1200; // 20 minutes
 
     private readonly IHttpClientFactory _httpClientFactory;
     private readonly ILogger<CmsTrackService> _logger;

DeepDrftManager/appsettings.json

@@ -8,5 +8,9 @@
   "AllowedHosts": "*",
   "ForwardedHeaders": {
     "DisableHttpsRedirection": false
+  },
+  "Upload": {
+    "IdleTimeoutSeconds": 90,
+    "ResponseTimeoutSeconds": 1200
   }
 }