fix: standardize aria-invalid handling across registration forms

Proposed changes

Standardize the aria-invalid attribute handling across the web-ui-registration package.

Currently, different forms use different implementations, including:

aria-invalid={errors.x ? 'true' : 'false'}
aria-invalid={errors.x ? 'true' : undefined}
aria-invalid={Boolean(errors.email)}
aria-invalid={errors?.email?.type === 'required'}

This results in inconsistent accessibility semantics across the registration, login, password reset, and email confirmation forms.

The recommended implementation is:

aria-invalid={errors.fieldName ? 'true' : undefined}

This avoids explicitly setting aria-invalid="false" before a field has actually been validated and provides consistent behavior across all affected fields.

Steps to reproduce :-

1. Open the packages/web-ui-registration package.
2. Inspect the form components that use aria-invalid.
3. Compare the implementations in:
   RegisterForm.tsx
   ResetPasswordPage.tsx
   LoginForm.tsx
   ResetPasswordForm.tsx
   EmailConfirmationForm.tsx
4. Observe that aria-invalid is implemented using multiple different patterns.
5. Trigger validation errors and inspect the rendered HTML/accessibility tree.
6. Observe that the resulting aria-invalid behavior differs between fields/forms.

Before proof

Currently, the package contains multiple implementations:

// Pattern 1
aria-invalid={errors.x ? 'true' : 'false'}

// Pattern 2
aria-invalid={errors.x ? 'true' : undefined}

// Pattern 3
aria-invalid={Boolean(errors.email)}

// Pattern 4
aria-invalid={errors?.email?.type === 'required'}

After proof

All affected fields should consistently use:

aria-invalid={errors.fieldName ? 'true' : undefined}

Start in packages/web-ui-registration and inspect aria-invalid usage in RegisterForm.tsx, ResetPasswordPage.tsx, LoginForm.tsx, ResetPasswordForm.tsx, and EmailConfirmationForm.tsx. Compare each affected field with the recommended error-based pattern, then trigger validation errors and inspect the rendered HTML or accessibility tree. Done means all affected fields use consistent aria-invalid behavior.