Allow mobile to natively trigger seeding an updated root

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When ob-go attempts to publish the new merkle root as a file has been updated, this update will retry for approximately 60 seconds before failing. We'd like to find a way that the root could continue to be retried after this failure without restarting the node (as the current root is always published on startup).

(This problem is not limited to the mobile case, however mobile users frequently experience intermittent network availability. These changes should consider the desktop experience as well.)

Some ideas:

• in the mobile case, the native client can detect the network availability and could trigger a republish attempt naïvely, letting the server check whether the root has changed and publish accordingly
• the server could also automatically retry on a continual basis (also ensuring the shutdown of the server does not get blocked if a change is waiting to be published)

This is a placeholder for future discussion and scoping.