fix: relax parsing of SCIM user 'active' flag to improve compatibility (#9296)

# Which Problems Are Solved
- Microsoft Entra invokes the user patch endpoint with `"active":
"True"` / `"active": "False"` when patching a user. This is a well-known
bug in MS Entra (see
[here](https://learn.microsoft.com/en-us/entra/identity/app-provisioning/application-provisioning-config-problem-scim-compatibility)),
but the bug fix has not landed yet and/or the feature flag does not
work.

# How the Problems Are Solved
- To ensure compatibility with MS Entra, the parsing of the the boolean
active flag of the scim user is relaxed and accepts strings in any
casing that resolve to `true` or `false` as well as raw boolean values.

# Additional Context
Part of https://github.com/zitadel/zitadel/issues/8140

internal/api/scim/resources/user.go

@@ -39,7 +39,7 @@ type ScimUser struct {
 	PreferredLanguage      language.Tag                  `json:"preferredLanguage,omitempty"`
 	Locale                 string                        `json:"locale,omitempty"`
 	Timezone               string                        `json:"timezone,omitempty"`
-	Active                 *bool                         `json:"active,omitempty"`
+	Active                 *scim_schemas.RelaxedBool     `json:"active,omitempty"`
 	Emails                 []*ScimEmail                  `json:"emails,omitempty" scim:"required"`
 	PhoneNumbers           []*ScimPhoneNumber            `json:"phoneNumbers,omitempty"`
 	Password               *scim_schemas.WriteOnlyString `json:"password,omitempty"`

internal/api/scim/resources/user_mapping.go

@@ -273,7 +273,7 @@ func (h *UsersHandler) mapToScimUser(ctx context.Context, user *query.User, md m
 			FamilyName: user.Human.LastName,
 			GivenName:  user.Human.FirstName,
 		},
-		Active: gu.Ptr(user.State.IsEnabled()),
+		Active: schemas.NewRelaxedBool(user.State.IsEnabled()),
 	}
 
 	if string(user.Human.Email) != "" {
@@ -311,7 +311,7 @@ func (h *UsersHandler) mapWriteModelToScimUser(ctx context.Context, user *comman
 			FamilyName: user.LastName,
 			GivenName:  user.FirstName,
 		},
-		Active: gu.Ptr(user.UserState.IsEnabled()),
+		Active: schemas.NewRelaxedBool(user.UserState.IsEnabled()),
 	}
 
 	if string(user.Email) != "" {

internal/api/scim/resources/user_patch_test.go

@@ -7,7 +7,6 @@ import (
 	"strings"
 	"testing"
 
-	"github.com/muhlemmer/gu"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 	"golang.org/x/text/language"
@@ -707,7 +706,7 @@ func TestOperationCollection_Apply(t *testing.T) {
 				PreferredLanguage: language.MustParse("en-US"),
 				Locale:            "en-US",
 				Timezone:          "America/New_York",
-				Active:            gu.Ptr(true),
+				Active:            schemas.NewRelaxedBool(true),
 				Emails: []*ScimEmail{
 					{
 						Value:   "jeanie.pendleton@example.com",