Provide syncoff mode to maintain watch stream without syncing in realtime sync mode

[chacha912]

Description:

In certain cases, users may want to maintain the watch stream without performing sync (push/pull) while performing other operations in the editor. Currently, using pause() results in the watch stream being disconnected, causing an unwatched event to occur and presence to disappear. In order to address this need where users want to maintain the watch stream without syncing in realtime mode, it is needed to introduce a syncoff mode.

Why:

To provide users with the flexibility to manage the watch stream without syncing in specific scenarios, improving the overall usability and experience of the product.