feat: portfolio of all my projects

/cartera (and GraphQL portfolio, REST /api/me/portfolio, MCP
get_portfolio) shows every active project I belong to (not archived, not
as a guest) at a glance: open, overdue, blocked and stuck tickets, the
sprint under way and whether it gets there, planned releases with their
forecast, and the open epics with their progress. It reuses the
dashboard's computations. A release with no tickets now reads «Sin
tickets» instead of «Todo hecho», here and on the dashboard.

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

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

@@ -0,0 +1,18 @@
+import { type } from '@ngrx/signals';
+import { eventGroup } from '@ngrx/signals/events';
+import { PortfolioProject } from '@task-stream/web/tracker/domain';
+
+export const portfolioPageEvents = eventGroup({
+  source: 'Portfolio Page',
+  events: {
+    opened: type<void>(),
+  },
+});
+
+export const portfolioApiEvents = eventGroup({
+  source: 'Portfolio API',
+  events: {
+    loaded: type<PortfolioProject[]>(),
+    loadFailed: type<string>(),
+  },
+});