List the live polling subscriptions for this key

Limited, machine-only release. Returns the live feeds bound to the authenticated customer and the exact API key making the request. A feed is live only while it is unrevoked and its bound key is unrevoked and unexpired, so a feed whose key has expired or been revoked stops being listed, and its account cap slot is free, without any row being deleted and without a background sweep. Revoked feeds are never listed: there is no include-revoked mode and no unbounded history. The response also reports the account-wide live count and the current per-account cap, because the cap counts every key's feeds on the account, not only this key's.