CMS Phase 9 Wave 3: Release Archive tab, medium selector, Session/Mix browsers

Renames Genre tab to Release Archive with switch-free medium card group
(Enum.GetValues-driven). Adds MediumFields single dispatch + CutFields/SessionFields/
MixFields per-medium sections embedded by all five upload/edit forms. BatchUpload
enforces single-track invariant for Session/Mix. Adds CmsSessionBrowser (hero-image
upload) and CmsMixBrowser (waveform status + per-row Generate trigger).
ICmsReleaseService/CmsReleaseService wraps api/release endpoints.
Note: medium selector is forward-compat only — API write path pending.

DeepDrftManager/Components/Pages/Tracks/TrackNew.razor

@@ -5,6 +5,7 @@
 @attribute [Authorize]
 
 @inject ICmsTrackService CmsTrackService
+@inject ICmsReleaseService CmsReleaseService
 @inject AuthenticationStateProvider AuthStateProvider
 @inject NavigationManager Navigation
 @inject ISnackbar Snackbar
@@ -32,6 +33,8 @@
             <MudTextField @bind-Value="_album" Label="Album" Variant="Variant.Outlined" />
             <MudTextField @bind-Value="_genre" Label="Genre" Variant="Variant.Outlined" />
 
+            <MediumFields @bind-Medium="_medium" @bind-ReleaseType="_releaseType" Disabled="_isUploading" />
+
             <MudField Label="Cover Art" Variant="Variant.Outlined" InnerPadding="false">
                 <MudStack Spacing="3">
                     @if (_selectedImageFile is { } selectedImage)
@@ -104,6 +107,8 @@
     private string _album = string.Empty;
     private string _genre = string.Empty;
     private string _releaseDate = string.Empty;
+    private ReleaseType _releaseType = ReleaseType.Single;
+    private ReleaseMedium _medium = ReleaseMedium.Cut;
     private string? _errorMessage;
     private bool _isUploading;
 
@@ -205,11 +210,24 @@
                 string.IsNullOrWhiteSpace(_releaseDate) ? null : _releaseDate,
                 _selectedFile.Name,
                 createdByUserId,
-                releaseType: ReleaseType.Single,
-                trackNumber: 1);
+                _releaseType,
+                trackNumber: 1,
+                _medium);
 
             if (result.Success)
             {
+                // Mix uploads fire the server-side high-res waveform trigger (§3.4) — the CMS computes
+                // nothing. Non-blocking: a failed trigger is recoverable from the Mixes browser.
+                if (_medium == ReleaseMedium.Mix && result.Value?.ReleaseId is { } mixReleaseId)
+                {
+                    var waveformResult = await CmsReleaseService.GenerateMixWaveformAsync(mixReleaseId);
+                    if (!waveformResult.Success)
+                    {
+                        Logger.LogWarning("TrackNew: mix waveform trigger failed for release {ReleaseId}", mixReleaseId);
+                        Snackbar.Add("Mix uploaded, but waveform generation failed. Retry from the Mixes browser.", Severity.Warning);
+                    }
+                }
+
                 // The upload endpoint does not accept an imagePath, so link the cover art with a
                 // follow-up metadata update — same two-step pattern TrackEdit uses.
                 if (_imagePath is { } imgPath && result.Value is { } created)