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/AlbumHeaderFields.razor

@@ -22,15 +22,6 @@
                           T="string" Label="Release Date (YYYY-MM-DD)" Placeholder="2024-01-15"
                           Variant="Variant.Outlined" Disabled="Disabled" />
         </MudItem>
-        <MudItem xs="12" sm="6">
-            <MudSelect T="ReleaseType" Value="ReleaseType" ValueChanged="@((ReleaseType v) => ReleaseTypeChanged.InvokeAsync(v))"
-                       Label="Release Type" Variant="Variant.Outlined" Disabled="Disabled">
-                @foreach (var rt in Enum.GetValues<ReleaseType>())
-                {
-                    <MudSelectItem T="ReleaseType" Value="rt">@rt</MudSelectItem>
-                }
-            </MudSelect>
-        </MudItem>
         <MudItem xs="12" sm="6">
             <MudField Label="Cover Art" Variant="Variant.Outlined" InnerPadding="false">
                 <MudStack Spacing="3">
@@ -70,6 +61,12 @@
             </MudField>
         </MudItem>
     </MudGrid>
+
+    <MudDivider Class="my-4" />
+
+    <MediumFields @bind-Medium="MediumBinding"
+                  @bind-ReleaseType="ReleaseTypeBinding"
+                  Disabled="Disabled" />
 </MudPaper>
 
 @code {
@@ -83,6 +80,8 @@
     [Parameter] public EventCallback<string> ReleaseDateChanged { get; set; }
     [Parameter] public ReleaseType ReleaseType { get; set; } = ReleaseType.Single;
     [Parameter] public EventCallback<ReleaseType> ReleaseTypeChanged { get; set; }
+    [Parameter] public ReleaseMedium Medium { get; set; } = ReleaseMedium.Cut;
+    [Parameter] public EventCallback<ReleaseMedium> MediumChanged { get; set; }
     [Parameter] public IBrowserFile? SelectedImageFile { get; set; }
     [Parameter] public EventCallback<IBrowserFile?> SelectedImageFileChanged { get; set; }
 
@@ -98,6 +97,20 @@
             ? null
             : $"/api/image/{Uri.EscapeDataString(ExistingImagePath)}";
 
+    // MediumFields uses two-way @bind; bridge its bindings to this component's own
+    // parameter/EventCallback pairs so the parent form stays the single owner of the values.
+    private ReleaseMedium MediumBinding
+    {
+        get => Medium;
+        set => MediumChanged.InvokeAsync(value);
+    }
+
+    private ReleaseType ReleaseTypeBinding
+    {
+        get => ReleaseType;
+        set => ReleaseTypeChanged.InvokeAsync(value);
+    }
+
     private Task HandleImageFileSelected(InputFileChangeEventArgs e) =>
         SelectedImageFileChanged.InvokeAsync(e.File);