fix: Add autofillHints to password field for Android autofill support

Adds autofillHints property with AutofillHints.password to the password
TextFormField in PasswordField widget. This enables password managers 
like Bitwarden to properly detect and autofill password fields on 
Android devices.

Without this hint, the Android autofill framework cannot identify the
field as a password input, preventing password managers from offering
autofill suggestions.

Changes:
- Added autofillHints: const [AutofillHints.password] to TextFormField
  in lib/widgets/auth/password_field.dart

Tested on Android with Bitwarden password manager.

lib/widgets/auth/password_field.dart

@@ -22,6 +22,7 @@ class _PasswordFieldState extends State<PasswordField> {
   Widget build(BuildContext context) {
     return TextFormField(
       key: const Key('inputPassword'),
+      autofillHints: const [AutofillHints.password],
       decoration: InputDecoration(
         labelText: AppLocalizations.of(context).password,
         prefixIcon: const Icon(Icons.password),