Add viewer-range categories, nomination tracking, dynamic showact form, session timeout, share URLs, and workflow-per-season

Features:
- Category viewer ranges + subcategory templates (admin group modal, tree workspace)
- Nomination enrichment via TwitchTracker API (NominationEnrichmentService,
  TwitchTrackerViewerStatsProvider) with admin tracking rules editor
- Nomination group tracker: CategoryGroupName as primary identifier,
  CategoryId stays as nullable legacy field; StreamerIdentity table
- Dynamic showact application form builder (AdminShowactFormBuilder,
  ShowactApplicationSchedule)
- Session idle timeout setting (AdminSessionTimeoutCard)
- Share URLs for X and Discord (SiteSettings, public extras)
- Workflow rules now stored per season (falls back to global SiteSettings)
- New admin routes: settings/access, settings/workflows, tracking-rules
- New admin review workspace with subcategory tabs
- AdminCategoriesView rebuilt with group/subcategory modals

Migrations (all additive):
- AddShareUrls, AddShowactDynamicForm, AddCategoryViewerRanges,
  AddSessionIdleTimeoutSettings, AddSeasonSubcategoryTemplates,
  AddNominationGroupTrackerIdentity, AddShowactApplicationSchedule,
  AddSeasonWorkflowRulesJson

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

frontend/src/components/admin/AdminContentPrivacySection.vue

@@ -31,9 +31,13 @@
           <p class="mt-2 text-lg font-semibold text-slate-900">{{ updatedLabel }}</p>
         </div>
       </div>
+      <label class="mt-6 block space-y-2">
+        <span class="text-xs font-semibold uppercase tracking-[0.18em] text-slate-500">Datenschutz E-Mail</span>
+        <input v-model="form.privacyEmail" type="email" placeholder="datenschutz@..." class="h-12 w-full rounded-2xl border border-violet-200 bg-white px-4 text-sm outline-none transition focus:border-violet-400 focus:ring-4 focus:ring-violet-100" />
+      </label>
       <AdminRichTextEditor
         v-model="form.privacyPolicyContent"
-        class="mt-6"
+        class="mt-4"
         label="Datenschutz Inhalt"
         placeholder="Datenschutztext..."
         min-height-class="min-h-[560px]"