Remove the fixed Account Type row from the profile page (closes #401)

The profile page showed "Account Type: Standard User" as fixed text,
even for admin, the account webhooker creates as its administrator.
webhooker has no account types, so the row is gone. The own-profile
test now checks that the page renders its Account Information section
without an Account Type row.

Model: opus-5-5

internal/handlers/profile_test.go

@@ -88,6 +88,8 @@ func TestHandleProfile_OwnProfile_OK(t *testing.T) {
 	h.HandleProfile().ServeHTTP(w, req)
 
 	assert.Equal(t, http.StatusOK, w.Code)
+	assert.Contains(t, w.Body.String(), "Account Information")
+	assert.NotContains(t, w.Body.String(), "Account Type")
 }
 
 func TestHandleProfile_OtherProfile_Forbidden(t *testing.T) {