During the authoritative commit of mergeChunks, to install only the chunks updated by mergeChunks, we need to introduce a new command that commits the merge operation in the global catalog.

Requirements:

• The command must accept the pre-commit ShardVersion as a parameter. This ShardVersion will be used to compute the updated chunk in case of retrying an already completed commit.
• The command must return a list of updated chunks. These chunks will later be persisted to the config.shard.catalog.chunks collection on shards.
• The command must be idempotent. The response must remain unchanged even if a previous attempt has already completed successfully.
• The command must support retryable writes and use the AlternativeClientRegion. This is required to enable replay protection, because MergeChunksCoordinator will send the command with a session id and an incremented transaction number to prevent lagging commands from being applied.
• The command must execute the global catalog commit (merge the given range and bump the shard version)