streamingccl: ensure destination tenant is garbage collected

[stevendanna]

To ensure that the destination cluster does not grow without bounds, we need to ensure that the ranges related to this tenant span are garbage collected. This likely requires that we:

• Periodically send a RecomputeStats RPC to every range we are ingesting into since we don't currently compute stats during AddSST.
• Provide the user some means to configure the TTL for the tenant. Span configurations from the source cluster may not be visible to the destination host since the tenant itself won't actually be running during the replication process.

Jira issue: CRDB-18529

Epic CRDB-19048

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cc @cockroachdb/bulk-io