Chore: Upgrade to Angular v18

Chore: Upgrade to Python 3.12
Chore: Upgrade to psycopg3

bookie/src/app/modifiers/modifier.resolver.ts

@@ -0,0 +1,11 @@
+import { inject } from '@angular/core';
+import { ResolveFn } from '@angular/router';
+
+import { Modifier } from '../core/modifier';
+
+import { ModifierService } from './modifier.service';
+
+export const modifierResolver: ResolveFn<Modifier> = (route) => {
+  const id = route.paramMap.get('id');
+  return inject(ModifierService).get(id);
+};