Align backend with frontend, make clips end-to-end, polish admin

Backend
- Add ClipSubmission entity + table (runtime bootstrapper) and
  POST /api/public/clips (server-derives platform from the link)
- Surface clip submissions in the admin season detail
- Add DELETE candidate/category/clip endpoints with audit entries

Frontend
- Clips admin: real moderation view (list, open link, delete) instead
  of placeholder; wired clipSubmissions through types/api/store
- Categories admin: add delete with confirm modal (matches Candidates)
- Voting ranking bar uses the unified purple gradient
- Fix ASCII transliterations to proper German umlauts across admin
- Remove orphan AdminView 2.vue

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

frontend/src/stores/awards.ts

@@ -179,6 +179,19 @@ const fallbackAdminSeasonDetail: AdminSeasonDetailResponse = {
       createdAt: '2026-06-17T08:00:00Z',
     },
   ],
+  clipSubmissions: [
+    {
+      id: 1,
+      categoryId: 1,
+      submittedByTwitchId: 'demo_user',
+      clipUrl: 'https://clips.twitch.tv/DemoClip',
+      title: 'Epischer Clutch im Finale',
+      creator: 'Hoshimi Miyu',
+      platform: 'Twitch',
+      status: 'pending',
+      createdAt: '2026-06-17T09:10:00Z',
+    },
+  ],
 }
 
 const emptyAdmin: AdminDashboardResponse = {
@@ -200,6 +213,7 @@ const emptyAdminSeasonDetail: AdminSeasonDetailResponse = {
   categories: [],
   candidates: [],
   pendingNominations: [],
+  clipSubmissions: [],
 }
 
 export const useAwardsStore = defineStore('awards', {
@@ -317,6 +331,11 @@ export const useAwardsStore = defineStore('awards', {
       await this.loadAdminSeasonDetail(seasonId)
       return result
     },
+    async deleteAdminClip(clipId: number, seasonId: number) {
+      const result = await api.deleteAdminClip(clipId)
+      await this.loadAdminSeasonDetail(seasonId)
+      return result
+    },
     async approveAdminNomination(nominationId: number, seasonId: number, payload: ApproveNominationPayload) {
       const result = await api.approveAdminNomination(nominationId, payload)
       await this.loadAdminSeasonDetail(seasonId)