feat: «Recordármelo», a reminder of a ticket only for me

On a ticket, «Recordármelo» offers in an hour, this evening, tomorrow or
next Monday at 9, in a week, or any date and time, with an optional note.
The ticket shows the waiting one («Te lo recordaré el mié 21 a las 9:00»)
to change or drop. Every minute a scheduler tells the ones whose time
came as a REMINDER notification (bell, push, e-mail), once, and forgets
those whose ticket went to the trash or out of reach. One per person and
ticket, private, no history (Mongo `issue_reminders`).

API: setReminder / clearReminder, Issue.myReminder, myReminders;
PUT/DELETE /api/issues/{issue}/reminder, GET /api/me/reminders. MCP:
remind_me.

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

libs/web/tracker/application/src/lib/events/issue.events.ts

@@ -50,6 +50,12 @@ export const issuePageEvents = eventGroup({
     watchRequested: type<{ issueId: string; watching: boolean }>(),
     pinRequested: type<{ issueId: string; pinned: boolean }>(),
     followTreeRequested: type<{ issueId: string; on: boolean }>(),
+    reminderRequested: type<{
+      issueId: string;
+      /** null: drop it. */
+      at: string | null;
+      note: string | null;
+    }>(),
     trashRequested: type<{
       issueId: string;
       trashed: boolean;

libs/web/tracker/application/src/lib/facades/issue.facade.ts

@@ -120,6 +120,17 @@ export class IssueFacade {
     );
   }
 
+  /** Remind me of the ticket then (null: drop it); one per ticket. */
+  setReminder(at: string | null, note: string | null = null): void {
+    this.withIssue((issueId) =>
+      this.dispatch.reminderRequested({
+        issueId,
+        at,
+        note: note?.trim() || null,
+      }),
+    );
+  }
+
   /** Follow the ticket with everything under it (an epic), or stop. */
   setFollowingTree(on: boolean): void {
     this.withIssue((issueId) =>

libs/web/tracker/application/src/lib/stores/issue.store.ts

@@ -22,6 +22,7 @@ import {
   IssueSummary,
   SprintsGateway,
   TrackerRealtimeGateway,
+  whenLabel,
 } from '@task-stream/web/tracker/domain';
 import {
   concatMap,
@@ -379,6 +380,26 @@ export const IssueStore = signalStore(
                   ),
             ),
           ),
+          events
+            .on(issuePageEvents.reminderRequested)
+            .pipe(
+              mergeMap(({ payload }) =>
+                runCommand(
+                  payload.at
+                    ? issues.setReminder(
+                        payload.issueId,
+                        payload.at,
+                        payload.note,
+                      )
+                    : issues.clearReminder(payload.issueId),
+                  payload.at
+                    ? `Te lo recordaré ${whenLabel(payload.at)}`
+                    : 'Recordatorio quitado',
+                  done,
+                  failed,
+                ),
+              ),
+            ),
           events
             .on(issuePageEvents.followTreeRequested)
             .pipe(