feat: User metadata (#2025)

* feat: user meta data events

* feat: user meta data set tests

* feat: user meta data tests

* feat: user meta data in protos

* feat: user meta data command api

* feat: user meta data query side

* feat: proto correct order, fix handlers

* feat: proto correct order

* feat: fixes of pr comments

* feat: fixes of pr comments

* feat: value as byte array

* feat: metadata feature

* Update internal/auth/repository/eventsourcing/handler/meta_data.go

Co-authored-by: Silvan <silvan.reusser@gmail.com>

* Update internal/command/user_meta_data.go

Co-authored-by: Silvan <silvan.reusser@gmail.com>

* Update proto/zitadel/metadata.proto

Co-authored-by: Silvan <silvan.reusser@gmail.com>

* Update proto/zitadel/metadata.proto

Co-authored-by: Silvan <silvan.reusser@gmail.com>

* fix: rename metadata files and table

* fix: rename meta data to metadat in protos

* Update internal/domain/metadata.go

Co-authored-by: Silvan <silvan.reusser@gmail.com>

* fix: rename vars

* fix: rebiuld docs

* Update internal/iam/repository/view/metadata_view.go

Co-authored-by: Silvan <silvan.reusser@gmail.com>

Co-authored-by: Silvan <silvan.reusser@gmail.com>

internal/repository/metadata/metadata.go

@@ -0,0 +1,92 @@
+package metadata
+
+import (
+	"encoding/json"
+
+	"github.com/caos/zitadel/internal/errors"
+	"github.com/caos/zitadel/internal/eventstore"
+	"github.com/caos/zitadel/internal/eventstore/repository"
+)
+
+const (
+	SetEventType     = "metadata.set"
+	RemovedEventType = "metadata.removed"
+)
+
+type SetEvent struct {
+	eventstore.BaseEvent `json:"-"`
+
+	Key   string `json:"key"`
+	Value []byte `json:"value"`
+}
+
+func (e *SetEvent) Data() interface{} {
+	return e
+}
+
+func (e *SetEvent) UniqueConstraints() []*eventstore.EventUniqueConstraint {
+	return nil
+}
+
+func NewSetEvent(
+	base *eventstore.BaseEvent,
+	key string,
+	value []byte,
+) *SetEvent {
+	return &SetEvent{
+		BaseEvent: *base,
+		Key:       key,
+		Value:     value,
+	}
+}
+
+func SetEventMapper(event *repository.Event) (eventstore.EventReader, error) {
+	e := &SetEvent{
+		BaseEvent: *eventstore.BaseEventFromRepo(event),
+	}
+
+	err := json.Unmarshal(event.Data, e)
+	if err != nil {
+		return nil, errors.ThrowInternal(err, "META-3n9fs", "unable to unmarshal metadata set")
+	}
+
+	return e, nil
+}
+
+type RemovedEvent struct {
+	eventstore.BaseEvent `json:"-"`
+
+	Key string `json:"key"`
+}
+
+func (e *RemovedEvent) Data() interface{} {
+	return e
+}
+
+func (e *RemovedEvent) UniqueConstraints() []*eventstore.EventUniqueConstraint {
+	return nil
+}
+
+func NewRemovedEvent(
+	base *eventstore.BaseEvent,
+	key string,
+) *RemovedEvent {
+
+	return &RemovedEvent{
+		BaseEvent: *base,
+		Key:       key,
+	}
+}
+
+func RemovedEventMapper(event *repository.Event) (eventstore.EventReader, error) {
+	e := &RemovedEvent{
+		BaseEvent: *eventstore.BaseEventFromRepo(event),
+	}
+
+	err := json.Unmarshal(event.Data, e)
+	if err != nil {
+		return nil, errors.ThrowInternal(err, "META-2m99f", "unable to unmarshal metadata removed")
+	}
+
+	return e, nil
+}