feat: create user scim v2 endpoint (#9132)

# Which Problems Are Solved
- Adds infrastructure code (basic implementation, error handling,
middlewares, ...) to implement the SCIM v2 interface
- Adds support for the user create SCIM v2 endpoint

# How the Problems Are Solved
- Adds support for the user create SCIM v2 endpoint under `POST
/scim/v2/{orgID}/Users`

# Additional Context

Part of #8140

internal/api/scim/resources/resource_handler.go

@@ -0,0 +1,61 @@
+package resources
+
+import (
+	"context"
+	"path"
+	"strconv"
+	"time"
+
+	"github.com/zitadel/zitadel/internal/api/authz"
+	"github.com/zitadel/zitadel/internal/api/http"
+	"github.com/zitadel/zitadel/internal/api/scim/schemas"
+	"github.com/zitadel/zitadel/internal/domain"
+)
+
+type ResourceHandler[T ResourceHolder] interface {
+	ResourceNameSingular() schemas.ScimResourceTypeSingular
+	ResourceNamePlural() schemas.ScimResourceTypePlural
+	SchemaType() schemas.ScimSchemaType
+	NewResource() T
+
+	Create(ctx context.Context, resource T) (T, error)
+}
+
+type Resource struct {
+	Schemas []schemas.ScimSchemaType `json:"schemas"`
+	Meta    *ResourceMeta            `json:"meta"`
+}
+
+type ResourceMeta struct {
+	ResourceType schemas.ScimResourceTypeSingular `json:"resourceType"`
+	Created      time.Time                        `json:"created"`
+	LastModified time.Time                        `json:"lastModified"`
+	Version      string                           `json:"version"`
+	Location     string                           `json:"location"`
+}
+
+type ResourceHolder interface {
+	GetResource() *Resource
+}
+
+func buildResource[T ResourceHolder](ctx context.Context, handler ResourceHandler[T], details *domain.ObjectDetails) *Resource {
+	created := details.CreationDate.UTC()
+	if created.IsZero() {
+		created = details.EventDate.UTC()
+	}
+
+	return &Resource{
+		Schemas: []schemas.ScimSchemaType{handler.SchemaType()},
+		Meta: &ResourceMeta{
+			ResourceType: handler.ResourceNameSingular(),
+			Created:      created,
+			LastModified: details.EventDate.UTC(),
+			Version:      strconv.FormatUint(details.Sequence, 10),
+			Location:     buildLocation(ctx, handler, details.ID),
+		},
+	}
+}
+
+func buildLocation[T ResourceHolder](ctx context.Context, handler ResourceHandler[T], id string) string {
+	return http.DomainContext(ctx).Origin() + path.Join(schemas.HandlerPrefix, authz.GetCtxData(ctx).OrgID, string(handler.ResourceNamePlural()), id)
+}