Add user reservation form feature

- Created new user-friendly reservation form component (prenotazione-form-user)
- Added getCurrentUser() method to UtenteAppService
- Added route /prenotazione/nuova for user reservation form
- Added Italian translations for new UI elements
- Form includes booking details and auto-populated user data
- Radio button toggle for private/company data display
- Form validation with required facility selection
- Created comprehensive documentation in frontend-changes.md

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

jhipster-jdl.jdl

@@ -144,6 +144,7 @@ enum Ruolo {
 
 relationship OneToOne {
   Prenotazione to Conferma
+  UtenteApp{internalUser(login)} to User with builtInEntity
 }