feat: templates per ticket type

Each ticket type can carry a starting description and a checklist, edited
in the project settings. New tickets of that type get the description
when they come without one and always get the checklist; the new ticket
form says what the template will add.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

libs/web/tracker/presenters/src/lib/pages/board.page.ts

@@ -342,10 +342,27 @@ const NOBODY = '__nobody__';
         </pi-text-field>
         <pi-textarea
           [formField]="f.description"
-          placeholder="Pasos para reproducir, criterios de aceptación…"
+          [placeholder]="
+            template()?.description ??
+            'Pasos para reproducir, criterios de aceptación…'
+          "
         >
           <pi-label>Descripción</pi-label>
         </pi-textarea>
+        @if (template(); as t) {
+          <p class="ts-muted ts-template-hint">
+            Plantilla de {{ typeLabel() }}:
+            @if (t.description) {
+              si dejas la descripción vacía se usará la de la plantilla
+            }
+            @if (t.description && t.checklist.length) {
+              ·
+            }
+            @if (t.checklist.length) {
+              se añadirá su checklist ({{ t.checklist.length }} pasos)
+            }
+          </p>
+        }
         @if (project.workflow().isDesignType(newType())) {
           <pi-text-field
             [formField]="f.figmaUrl"
@@ -641,6 +658,17 @@ export class BoardPage {
 
   /* New ticket */
   protected readonly newType = signal<string>('');
+  /** The template the new ticket will get (the API applies it). */
+  protected readonly template = computed(
+    () =>
+      this.project
+        .workflow()
+        .settings.issueTypes.find((t) => t.id === this.newType())?.template ??
+      null,
+  );
+  protected readonly typeLabel = computed(
+    () => typeLook(this.project.workflow(), this.newType()).label,
+  );
   private readonly model = signal({
     title: '',
     description: '',