Add winner archive, host image upload and live demo data

Deliver the demo-ready feature set and seed data so the live site can be
presented end to end:

- Winner archive: ArchivedWinner domain, admin CRUD endpoints/view/manager
  and public archive surface, backed by AddArchivedWinners migration.
- Host presentation: host image upload and artist name on SiteSettings with
  public image endpoint and supporting migrations.
- Clip submissions: idempotent table-ensure migration plus current-season
  demo clips for review workflows.
- Demo seed data: sponsors, share links and 2025 archived winners, with a
  guarded RemoveDemoSeasons cleanup; all seeds guard against real data.
- EnsureRuntimeSchemaParity migration to align runtime schema defensively.
- Admin/home UI refinements; remove unused team role permissions modal and
  dead share-quick-links code.

All seed and schema migrations are idempotent (IF NOT EXISTS / ON CONFLICT)
and skip when real season data is present.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

frontend/src/components/home/HomeNominationWizardPane.vue

@@ -3,11 +3,7 @@ const props = defineProps<{
   categoryName: string
   links: string[]
   errors: string[]
-  visibleLinkCount: number
-  remainingLinkCount: number
   onLinkInput: (index: number, value: string) => void
-  onAddLinkField: () => void
-  onRemoveLinkField: (index: number) => void
 }>()
 </script>
 
@@ -20,17 +16,9 @@ const props = defineProps<{
     </header>
 
     <div class="home-nomination-pane__fields">
-      <label v-for="(_, index) in props.links.slice(0, props.visibleLinkCount)" :key="index" class="home-nomination-field">
+      <label v-for="(_, index) in props.links" :key="index" class="home-nomination-field">
         <span class="home-nomination-field__header">
           <span>{{ index === 0 ? 'Link 1' : `Link ${index + 1} optional` }}</span>
-          <button
-            v-if="index > 0"
-            type="button"
-            class="home-nomination-field__remove"
-            @click.prevent="props.onRemoveLinkField(index)"
-          >
-            Entfernen
-          </button>
         </span>
         <input
           :value="props.links[index]"
@@ -44,16 +32,5 @@ const props = defineProps<{
         <small v-else>Offizieller Kanal- oder Stream-Link.</small>
       </label>
     </div>
-
-    <button
-      v-if="props.remainingLinkCount > 0"
-      type="button"
-      class="home-nomination-pane__add-link"
-      @click="props.onAddLinkField"
-    >
-      <span>+ Weiteren Link hinzufügen</span>
-      <small>Noch {{ props.remainingLinkCount }} möglich</small>
-    </button>
-
   </section>
 </template>