Add endpoint to connection code snippets

[artemmufazalov]

After #1367 is finished and ydb-platform/ydb#13279 is fixed.

ControlPlane.endpoint field from meta/cp_databases should be added in connection code snippets instead of just "endpoint" string

[antonkovalenko]

в созданной базе нет в user attributes ее id

[artemmufazalov]

It requires ydb-platform/ydb#16389 to be in our production meta

[artemmufazalov]

For domain db Connect to DB button should not be shown in schema tree actions. We request DB data once for tenant page