[misc] Move shared components to shared directory (#4286)

Moved the following directories:

```
  - management/client → shared/management/client
  - management/domain → shared/management/domain
  - management/proto → shared/management/proto
  - signal/client → shared/signal/client
  - signal/proto → shared/signal/proto
  - relay/client → shared/relay/client
  - relay/auth → shared/relay/auth
```

and adjusted import paths

shared/management/client/rest/groups.go

@@ -0,0 +1,92 @@
+package rest
+
+import (
+	"bytes"
+	"context"
+	"encoding/json"
+
+	"github.com/netbirdio/netbird/management/server/http/api"
+)
+
+// GroupsAPI APIs for Groups, do not use directly
+type GroupsAPI struct {
+	c *Client
+}
+
+// List list all groups
+// See more: https://docs.netbird.io/api/resources/groups#list-all-groups
+func (a *GroupsAPI) List(ctx context.Context) ([]api.Group, error) {
+	resp, err := a.c.NewRequest(ctx, "GET", "/api/groups", nil, nil)
+	if err != nil {
+		return nil, err
+	}
+	if resp.Body != nil {
+		defer resp.Body.Close()
+	}
+	ret, err := parseResponse[[]api.Group](resp)
+	return ret, err
+}
+
+// Get get group info
+// See more: https://docs.netbird.io/api/resources/groups#retrieve-a-group
+func (a *GroupsAPI) Get(ctx context.Context, groupID string) (*api.Group, error) {
+	resp, err := a.c.NewRequest(ctx, "GET", "/api/groups/"+groupID, nil, nil)
+	if err != nil {
+		return nil, err
+	}
+	if resp.Body != nil {
+		defer resp.Body.Close()
+	}
+	ret, err := parseResponse[api.Group](resp)
+	return &ret, err
+}
+
+// Create create new group
+// See more: https://docs.netbird.io/api/resources/groups#create-a-group
+func (a *GroupsAPI) Create(ctx context.Context, request api.PostApiGroupsJSONRequestBody) (*api.Group, error) {
+	requestBytes, err := json.Marshal(request)
+	if err != nil {
+		return nil, err
+	}
+	resp, err := a.c.NewRequest(ctx, "POST", "/api/groups", bytes.NewReader(requestBytes), nil)
+	if err != nil {
+		return nil, err
+	}
+	if resp.Body != nil {
+		defer resp.Body.Close()
+	}
+	ret, err := parseResponse[api.Group](resp)
+	return &ret, err
+}
+
+// Update update group info
+// See more: https://docs.netbird.io/api/resources/groups#update-a-group
+func (a *GroupsAPI) Update(ctx context.Context, groupID string, request api.PutApiGroupsGroupIdJSONRequestBody) (*api.Group, error) {
+	requestBytes, err := json.Marshal(request)
+	if err != nil {
+		return nil, err
+	}
+	resp, err := a.c.NewRequest(ctx, "PUT", "/api/groups/"+groupID, bytes.NewReader(requestBytes), nil)
+	if err != nil {
+		return nil, err
+	}
+	if resp.Body != nil {
+		defer resp.Body.Close()
+	}
+	ret, err := parseResponse[api.Group](resp)
+	return &ret, err
+}
+
+// Delete delete group
+// See more: https://docs.netbird.io/api/resources/groups#delete-a-group
+func (a *GroupsAPI) Delete(ctx context.Context, groupID string) error {
+	resp, err := a.c.NewRequest(ctx, "DELETE", "/api/groups/"+groupID, nil, nil)
+	if err != nil {
+		return err
+	}
+	if resp.Body != nil {
+		defer resp.Body.Close()
+	}
+
+	return nil
+}