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/api/tracker/domain/src/lib/project/project-settings.spec.ts

@@ -99,6 +99,29 @@ describe('Project settings', () => {
     );
   });
 
+  it('keeps a template per type, only when it says something', () => {
+    const project = newProject();
+    const settings = defaultProjectSettings();
+    settings.issueTypes[0].template = {
+      description: '  ## Pasos para reproducir  ',
+      checklist: [' Probar en Safari ', ''],
+    };
+    settings.issueTypes[1].template = { description: ' ', checklist: [] };
+    project.updateSettings('owner', settings);
+
+    expect(project.workflow.templateOf('BUG')).toEqual({
+      description: '## Pasos para reproducir',
+      checklist: ['Probar en Safari'],
+    });
+    expect(project.workflow.templateOf('FEATURE')).toBeNull();
+    const tooLong = defaultProjectSettings();
+    tooLong.issueTypes[0].template = {
+      description: null,
+      checklist: Array.from({ length: 21 }, (_, i) => `Paso ${i}`),
+    };
+    expect(() => project.updateSettings('owner', tooLong)).toThrow(/plantilla/);
+  });
+
   it('keeps work-in-progress limits, from 1 to 999', () => {
     const project = newProject();
     const limited = defaultProjectSettings();

libs/api/tracker/domain/src/lib/project/project-settings.ts

@@ -68,14 +68,26 @@ export interface WorkflowStatus {
   wipLimit?: number | null;
 }
 
+/** What a new ticket of a type starts with. */
+export interface IssueTemplate {
+  /** Used when the ticket comes without a description. */
+  description: string | null;
+  /** Steps added to every new ticket of the type. */
+  checklist: string[];
+}
+
 export interface IssueTypeOption {
   id: string;
   name: string;
   icon: TypeIcon;
   color: SettingColor;
   archived: boolean;
+  template?: IssueTemplate;
 }
 
+export const MAX_TEMPLATE_DESCRIPTION = 5000;
+export const MAX_TEMPLATE_STEPS = 20;
+
 export interface AreaOption {
   id: string;
   name: string;
@@ -198,6 +210,13 @@ export class ProjectWorkflow {
     return this.settings.statuses.find((s) => s.id === id);
   }
 
+  /** What a new ticket of the type starts with, if anything. */
+  templateOf(typeId: string): IssueTemplate | null {
+    return (
+      this.settings.issueTypes.find((t) => t.id === typeId)?.template ?? null
+    );
+  }
+
   /** Most tickets the status should hold (null: no limit). */
   wipLimit(id: string): number | null {
     return this.status(id)?.wipLimit ?? null;
@@ -300,13 +319,18 @@ export function validateProjectSettings(
     // Only when set: settings saved unchanged must compare equal.
     ...(s.wipLimit != null ? { wipLimit: s.wipLimit } : {}),
   }));
-  const issueTypes = next.issueTypes.map((t) => ({
-    id: normId(t.id),
-    name: normName(t.name),
-    icon: t.icon,
-    color: t.color,
-    archived: !!t.archived,
-  }));
+  const issueTypes = next.issueTypes.map((t) => {
+    const template = normTemplate(t.template);
+    return {
+      id: normId(t.id),
+      name: normName(t.name),
+      icon: t.icon,
+      color: t.color,
+      archived: !!t.archived,
+      // Only when there is one: settings saved unchanged must compare equal.
+      ...(template ? { template } : {}),
+    };
+  });
   const areas = next.areas.map((a) => ({
     id: normId(a.id),
     name: normName(a.name),
@@ -393,6 +417,26 @@ export function validateProjectSettings(
   return { statuses, transitions, issueTypes, areas };
 }
 
+function normTemplate(
+  template: IssueTemplate | undefined,
+): IssueTemplate | null {
+  const description = template?.description?.trim() || null;
+  const checklist = (template?.checklist ?? [])
+    .map((step) => step.trim())
+    .filter(Boolean);
+  if (!description && !checklist.length) return null;
+  assertThat(
+    (description?.length ?? 0) <= MAX_TEMPLATE_DESCRIPTION,
+    `Una plantilla tiene como mucho ${MAX_TEMPLATE_DESCRIPTION} caracteres`,
+  );
+  assertThat(
+    checklist.length <= MAX_TEMPLATE_STEPS &&
+      checklist.every((step) => step.length <= 300),
+    `Una plantilla tiene como mucho ${MAX_TEMPLATE_STEPS} pasos de 300 caracteres`,
+  );
+  return { description, checklist };
+}
+
 function normId(id: string): string {
   const value = (id ?? '').trim().toUpperCase();
   assertThat(