Description

This PR adds required msg for SP exit.

SP graceful exit process:

1. The SP which wants to exit to send a tx with MsgStorageProviderExit, it is status will become STATUS_GRACEFUL_EXITING
2. All other SPs are encouraged to be the successors of the exiting SP's Global Virtual Group family(GVGF) as primary SP, or Global Virtual group(GVG) as secondary. They can send a tx with MsgReserveSwapIn to reserve the position.
3. Once successor got all data stored properly. They will send a tx with MsgCompleteSwapIn to ack the success, within GVGF/GVG, SP replacement will take place.
4. If the SP has no more GVGF/GVG related, anyone can send a tx with MsgCompleteStorageProviderExit to complete such SP's exit, deposit onto Greenfield will be refund to the exit SP.

SP forced exit process:

A uncooperative SP refuses to provide service will be put into STATUS_FORCED_EXITING executing MsgStorageProviderForceExit via governance. Other SP would do the same as above step 2-3. Eventually,
If the SP has no more GVGF/GVG related, anyone can send a tx with MsgCompleteStorageProviderExit to complete such SP's exit, deposit onto Greenfield will be transfer to payment module account.

Modification to current Msgs:

MsgCompleteStorageProviderExit. Anyone can trigger the tx for a graceful_exit or forced_exit SP to complete the exit process. Previous deposit onto Greenfield will be refund to the exit SP or transferred to gov module.

MsgUpdateBucketInfo. When a SP is in STATUS_GRACEFUL_EXITING or STATUS_FORCED_EXITING, buckets it served will not be allowed to update(quota).

MsgDiscontinueObject. A successor primary SP can discontinue objects that the exititng SP serves.

Rationale

Example

add an example CLI or API response...

Changes

Notable changes:

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Potential Impacts

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