feat(channel): identite chaine partagee cliquable partout + logos fiabilises

- Nouveau app-channel-identity (avatar+nom -> /channel, fallback resolve /api/channels, initiales sinon)
- ProviderBadge: accepte les ids courts yt/dm/tw/pt/od/ru
- Search adapters yt/dm/pt/od: conservent channelExternalId/channelAvatarUrl (pt derive instance|channel)
- video-card/themes/watch/related/suggestions/subscriptions/channel-header uniformises sur l'identite partagee

src/components/themes/provider-theme-page.component.ts

@@ -10,6 +10,7 @@ import { TranslatePipe } from '../../pipes/translate.pipe';
 import { LikeButtonComponent } from '../shared/components/like-button/like-button.component';
 import { DurationPipe } from '../../app/shared/pipes/duration.pipe';
 import { ProviderBadgeComponent } from '../../app/shared/components/provider-badge/provider-badge.component';
+import { ChannelIdentityComponent } from '../../app/shared/components/channel-identity/channel-identity.component';
 import { classifyVideo, isShortVideo } from '../../app/shared/utils/video-kind';
 import { map, of, switchMap, catchError, Observable } from 'rxjs';
 import { PagedResult } from '../../services/youtube-api.service';
@@ -46,7 +47,7 @@ const TWITCH_THEME_KEYWORDS: Record<string, string[]> = {
   standalone: true,
   templateUrl: './provider-theme-page.component.html',
   changeDetection: ChangeDetectionStrategy.OnPush,
-  imports: [CommonModule, FormsModule, RouterLink, TranslatePipe, LikeButtonComponent, DurationPipe, ProviderBadgeComponent]
+  imports: [CommonModule, FormsModule, RouterLink, TranslatePipe, LikeButtonComponent, DurationPipe, ProviderBadgeComponent, ChannelIdentityComponent]
 })
 export class ProviderThemePageComponent implements OnDestroy {
   private route = inject(ActivatedRoute);