Add instructions for creating a new Angular component

Expanded setup guidelines with steps to generate a new component in Angular. Detailed instructions include modifications to the component, app module, and routes for proper integration.

frontend/setup.md

@@ -1,2 +1,11 @@
 - https://nodejs.org/en
 - npm install -g @angular/cli
+
+# New page
+
+- ng generate component <name>
+- Go to the component (<name>.component.ts)
+- add standalone: false to the @Component
+- remove imports: [] from that same block
+- Go to app.module.ts and add the new page in declaration
+- Add the new file to routes and give it a path (like 'new_page')