fix(storage, web): clean up stream handlers on "hot restart"

[russellwheatley]

Description

1. This commit fixed an issue where stream was being recreated again (on task.pause() it was calling snapshotEvents again). Also fixed task.pause() so it paused when paused state came through. Also throwing exception.
2. Usual clean up on "hot restart" of stream handlers.

Related Issues

closes: #7064

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