feat: guest role for clients and outsiders

A project member can be a GUEST. In a private project a guest only sees
the tickets they take part in (opened, assigned or followed): every other
ticket answers 404, also in my work, realtime changes, blockers and
linked tickets, and project-wide views (activity, statistics, dashboard,
releases, sprints, epics, trash) answer 403. Guests open tickets without
assigning or planning them, and comment, attach, follow and vote on their
own; they change nothing else. In a public project they see what anyone
does. The web gives them only Tablero, Lista and Miembros and loads none
of the project-wide data.

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

libs/api/tracker/application/src/lib/queries/can-view-project.query-handler.ts

@@ -9,6 +9,11 @@ export class CanViewProjectQueryHandler
   constructor(private readonly access: ReadAccess) {}
 
   async execute(query: CanViewProjectQuery): Promise<boolean> {
-    return this.access.canView(query.projectId, query.viewerId);
+    if (!(await this.access.canView(query.projectId, query.viewerId)))
+      return false;
+    return (
+      !query.wholeProject ||
+      !(await this.access.participantScope(query.projectId, query.viewerId))
+    );
   }
 }