A wrapper around a Stream of PeekResponseUnary that records when it sees the
first row data in the given histogram. It also keeps track of whether we have already observed
the end of the underlying stream.
Renders SQL for statement arrival logging: parsed and displayed with its
literals redacted, which is the same redaction the statement log applies.
When the text does not parse or exceeds the statement batch size limit, a
placeholder with the byte length is returned. Raw text is never returned,
so a statement that crashes the parser is not captured, an accepted
limitation.