feat: release notes

Each release can carry notes in Markdown, written before or after it
ships. A draft is generated from its finished tickets grouped by type, to
edit and copy from the releases page.

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

libs/api/tracker/application/src/lib/event-handlers/activity-summary.ts

@@ -25,6 +25,7 @@ import {
   ProjectUpdatedEvent,
   ProjectWorkflow,
   ReleaseArchivedEvent,
+  ReleaseNotesWrittenEvent,
   ReleaseCreatedEvent,
   ReleaseShippedEvent,
   ReleaseUpdatedEvent,
@@ -191,6 +192,10 @@ export function describeEvent(
     return `${actor} actualizó la release ${ctx.releaseName}`;
   if (event instanceof ReleaseShippedEvent)
     return `${actor} publicó la release ${ctx.releaseName} 🚀`;
+  if (event instanceof ReleaseNotesWrittenEvent)
+    return event.notes
+      ? `${actor} escribió las notas de la release ${ctx.releaseName}`
+      : `${actor} quitó las notas de la release ${ctx.releaseName}`;
   if (event instanceof ReleaseArchivedEvent)
     return `${actor} archivó la release ${ctx.releaseName}`;
   const sprint = ctx.sprintName || 'un sprint';