cherry-pick: feat: improve observability for subscription/cursor SHOW commands (#18896)

[hzxa21]

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What's changed and what's your intention?

After #19264

Checklist

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[graphite-app]

Graphite Automations

"release branch request review" took an action on this PR • (11/05/24)

1 reviewer was added to this PR based on xxchan's automation.