Migration Angular 20 -> 21 : fin de la migration securite (0 vulnerabilite npm)

- ng update @angular/core@21 @angular/cli@21 (corrige GHSA-jrmj-c5cx-3cw6, XSS SVG)
- Migration automatique des templates vers le control flow natif (@if/@for, 138 fichiers)
- Correction des 5 `track` invalides generes par la migration (trackBy a 1 argument
  -> track $index) + suppression des fonctions trackBy mortes
- TypeScript 5.9, zone.js 0.15 ; npm audit : 0 vulnerabilite

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

web/src/app/campaigns/character/character-edit/character-edit.component.ts

@@ -1,5 +1,5 @@
 import { Component, OnInit } from '@angular/core';
-import { CommonModule } from '@angular/common';
+
 import { ActivatedRoute, Router } from '@angular/router';
 import { FormsModule } from '@angular/forms';
 import { LucideAngularModule, Save, ArrowLeft, User, Trash2, Sparkles } from 'lucide-angular';
@@ -26,7 +26,7 @@ import { ConfirmDialogService } from '../../../shared/confirm-dialog/confirm-dia
  */
 @Component({
     selector: 'app-character-edit',
-    imports: [CommonModule, FormsModule, LucideAngularModule, AiChatDrawerComponent, DynamicFieldsFormComponent, SingleImagePickerComponent],
+    imports: [FormsModule, LucideAngularModule, AiChatDrawerComponent, DynamicFieldsFormComponent, SingleImagePickerComponent],
     templateUrl: './character-edit.component.html',
     styleUrls: ['./character-edit.component.scss']
 })