Improve admin candidate modal UX and add clip menu visibility toggle

- Widen AdminCandidateEditorModal to size lg for better readability
- Rename "Clip-Compilation" section to "Clip / Compilation", update copy to reflect single clips too, drop upload hint and Clip-Plattform field, rename label to "Link"
- Fix NativeSelect dropdown clipping inside overflow-y-auto modals by teleporting the menu to body with fixed positioning, flip-up logic, and dynamic maxHeight capped to viewport
- Add ClipAdminMenuVisible setting (backend domain, contracts, endpoint, migration) with matching frontend types, defaults, form wiring, and toggle in the Clip-Workflow modal — hides the Clips nav item from the admin sidebar when disabled

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Backend/Endpoints/AdminSiteSettingsEndpoints.cs

@@ -13,6 +13,7 @@ public static class AdminSiteSettingsEndpoints
 {
     private const string FallbackMaintenanceTitle = "Sternenpause";
     private const string FallbackMaintenanceMessage = "Die Award-Galaxie wird gerade liebevoll poliert. Schau gleich wieder vorbei.";
+    private const string FallbackClipSubmissionDisabledMessage = "Clip-Einreichungen sind aktuell geschlossen.";
 
     public static RouteGroupBuilder MapAdminSiteSettingsEndpoints(this RouteGroupBuilder group)
     {
@@ -32,6 +33,14 @@ public static class AdminSiteSettingsEndpoints
             .AddEndpointFilter((context, next) => AdminEndpointConventions.RequireWritePermission(context, next, AdminPermissionCatalog.Settings))
             .WithName("UpdateAdminOperationalSettings")
             .WithOpenApi();
+        group.MapGet("/optional-feature-settings", GetOptionalFeatureSettings)
+            .AddEndpointFilter((context, next) => AdminEndpointConventions.RequirePermission(context, next, AdminPermissionCatalog.Settings))
+            .WithName("GetAdminOptionalFeatureSettings")
+            .WithOpenApi();
+        group.MapPut("/optional-feature-settings", UpdateOptionalFeatureSettings)
+            .AddEndpointFilter((context, next) => AdminEndpointConventions.RequireWritePermission(context, next, AdminPermissionCatalog.Settings))
+            .WithName("UpdateAdminOptionalFeatureSettings")
+            .WithOpenApi();
         return group;
     }
 
@@ -57,6 +66,8 @@ public static class AdminSiteSettingsEndpoints
             settings.ContactContent,
             settings.SponsorsUrl,
             settings.SponsorsContent,
+            settings.ShowactsUrl,
+            settings.ShowactsContent,
             SeasonMappings.ReadSocialLinks(settings),
             SeasonMappings.ReadFaqItems(settings)));
     }
@@ -100,6 +111,8 @@ public static class AdminSiteSettingsEndpoints
         settings.ContactContent = request.ContactContent.Trim();
         settings.SponsorsUrl = normalizedUrls.SponsorsUrl;
         settings.SponsorsContent = request.SponsorsContent.Trim();
+        settings.ShowactsUrl = normalizedUrls.ShowactsUrl;
+        settings.ShowactsContent = request.ShowactsContent.Trim();
         settings.SocialLinksJson = JsonSerializer.Serialize(socialLinks);
         settings.FaqJson = JsonSerializer.Serialize(request.Faq ?? []);
 
@@ -133,7 +146,8 @@ public static class AdminSiteSettingsEndpoints
         if (!TryNormalizePublicUrl(request.NewsletterUrl, "Newsletter-Link", out var newsletterUrl, out var errorMessage)
             || !TryNormalizePublicUrl(request.ImprintUrl, "Impressum-Link", out var imprintUrl, out errorMessage)
             || !TryNormalizePublicUrl(request.ContactUrl, "Kontakt-Link", out var contactUrl, out errorMessage)
-            || !TryNormalizePublicUrl(request.SponsorsUrl, "Sponsoren-Link", out var sponsorsUrl, out errorMessage))
+            || !TryNormalizePublicUrl(request.SponsorsUrl, "Sponsoren-Link", out var sponsorsUrl, out errorMessage)
+            || !TryNormalizePublicUrl(request.ShowactsUrl, "Showact-Link", out var showactsUrl, out errorMessage))
         {
             return Results.BadRequest(new { message = errorMessage });
         }
@@ -144,6 +158,7 @@ public static class AdminSiteSettingsEndpoints
             ImprintUrl = imprintUrl,
             ContactUrl = contactUrl,
             SponsorsUrl = sponsorsUrl,
+            ShowactsUrl = showactsUrl,
         };
 
         var normalizedSocialLinks = new List<PublicSocialLinkDto>();
@@ -187,6 +202,108 @@ public static class AdminSiteSettingsEndpoints
         public string ImprintUrl { get; set; } = string.Empty;
         public string ContactUrl { get; set; } = string.Empty;
         public string SponsorsUrl { get; set; } = string.Empty;
+        public string ShowactsUrl { get; set; } = string.Empty;
+    }
+
+    private static async Task<IResult> GetOptionalFeatureSettings(AwardsDbContext db)
+    {
+        var settings = await db.SiteSettings.AsNoTracking().FirstOrDefaultAsync(item => item.Id == 1);
+        if (settings is null)
+        {
+            return Results.NotFound();
+        }
+
+        return Results.Ok(ToOptionalFeatureSettingsResponse(settings));
+    }
+
+    private static async Task<IResult> UpdateOptionalFeatureSettings(
+        HttpContext context,
+        UpdateOptionalFeatureSettingsRequest request,
+        AwardsDbContext db,
+        IAdminAuditService adminAuditService)
+    {
+        var session = AdminEndpointConventions.CurrentSession(context);
+        var settings = await db.SiteSettings.FirstOrDefaultAsync(item => item.Id == 1);
+        if (settings is null)
+        {
+            return Results.NotFound();
+        }
+
+        var before = ToOptionalFeatureSettingsResponse(settings);
+        var disabledMessage = NormalizeOptionalFeatureText(
+            request.ClipSubmissionDisabledMessage,
+            FallbackClipSubmissionDisabledMessage,
+            240);
+        var showactDisabledMessage = NormalizeOptionalFeatureText(
+            request.ShowactApplicationDisabledMessage,
+            "Showact-Bewerbungen sind aktuell geschlossen.",
+            240);
+
+        settings.ClipSubmissionsEnabled = request.ClipSubmissionsEnabled;
+        settings.ClipReviewEnabled = request.ClipReviewEnabled;
+        settings.ClipAdminMenuVisible = request.ClipAdminMenuVisible;
+        settings.ClipSubmissionDisabledMessage = disabledMessage;
+        settings.ShowactApplicationsEnabled = request.ShowactApplicationsEnabled;
+        settings.ShowactApplicationDisabledMessage = showactDisabledMessage;
+        settings.SponsorsVisible = request.SponsorsVisible;
+
+        var after = ToOptionalFeatureSettingsResponse(settings);
+        adminAuditService.AddEntry(
+            session.TwitchUserId,
+            "optional-features.update",
+            "site-settings",
+            settings.Id.ToString(),
+            "Optionale Workflow-Features wurden aktualisiert.",
+            new
+            {
+                before,
+                after,
+                changes = BuildOptionalFeatureChanges(before, after),
+            },
+            RequestMetadataReader.Read(context));
+
+        await db.SaveChangesAsync(context.RequestAborted);
+        return Results.Ok(after);
+    }
+
+    private static AdminOptionalFeatureSettingsResponse ToOptionalFeatureSettingsResponse(SiteSettings settings) =>
+        new(
+            settings.ClipSubmissionsEnabled,
+            settings.ClipReviewEnabled,
+            settings.ClipAdminMenuVisible,
+            string.IsNullOrWhiteSpace(settings.ClipSubmissionDisabledMessage)
+                ? FallbackClipSubmissionDisabledMessage
+                : settings.ClipSubmissionDisabledMessage,
+            settings.ShowactApplicationsEnabled,
+            string.IsNullOrWhiteSpace(settings.ShowactApplicationDisabledMessage)
+                ? "Showact-Bewerbungen sind aktuell geschlossen."
+                : settings.ShowactApplicationDisabledMessage,
+            settings.SponsorsVisible);
+
+    private static string NormalizeOptionalFeatureText(string? value, string fallback, int maxLength)
+    {
+        var trimmed = (value ?? string.Empty).Trim();
+        if (string.IsNullOrWhiteSpace(trimmed))
+        {
+            return fallback;
+        }
+
+        return trimmed.Length <= maxLength ? trimmed : trimmed[..maxLength];
+    }
+
+    private static object[] BuildOptionalFeatureChanges(
+        AdminOptionalFeatureSettingsResponse before,
+        AdminOptionalFeatureSettingsResponse after)
+    {
+        var changes = new List<object>();
+        AddOperationalChange(changes, "clipSubmissionsEnabled", "Clip-Einreichung", before.ClipSubmissionsEnabled, after.ClipSubmissionsEnabled);
+        AddOperationalChange(changes, "clipReviewEnabled", "Clip-Review", before.ClipReviewEnabled, after.ClipReviewEnabled);
+        AddOperationalChange(changes, "clipAdminMenuVisible", "Clips-Menüpunkt", before.ClipAdminMenuVisible, after.ClipAdminMenuVisible);
+        AddOperationalChange(changes, "clipSubmissionDisabledMessage", "Deaktiviert-Hinweis", before.ClipSubmissionDisabledMessage, after.ClipSubmissionDisabledMessage);
+        AddOperationalChange(changes, "showactApplicationsEnabled", "Showact-Bewerbungen", before.ShowactApplicationsEnabled, after.ShowactApplicationsEnabled);
+        AddOperationalChange(changes, "showactApplicationDisabledMessage", "Showact-Hinweis", before.ShowactApplicationDisabledMessage, after.ShowactApplicationDisabledMessage);
+        AddOperationalChange(changes, "sponsorsVisible", "Sponsoren sichtbar", before.SponsorsVisible, after.SponsorsVisible);
+        return changes.ToArray();
     }
 
     private static async Task<IResult> GetOperationalSettings(AwardsDbContext db, IConfiguration configuration)