Chore: Upgrade to Angular v18

Chore: Upgrade to Python 3.12
Chore: Upgrade to psycopg3

bookie/src/app/users/user-list.resolver.ts

@@ -0,0 +1,10 @@
+import { inject } from '@angular/core';
+import { ResolveFn } from '@angular/router';
+
+import { User } from '../core/user';
+
+import { UserService } from './user.service';
+
+export const userListResolver: ResolveFn<User[]> = () => {
+  return inject(UserService).list();
+};