What a span is of: a definition (its hash) by its name now, or, no longer named (`gone`): if a version named now replaced it, an earlier version of that definition, by its name (`earlier`: changed since, not renamed or removed); if not, by the name it had. A page's or a statement's (no hash) by its name.
The errors since `since` (the server's and pages', not a call as the page saw it, which is the server's again), by the definition that threw them as named now (each version of it alike) and what they said, alike, the most often first: an error each span it went up through says is one error, once a trace. Each with when it was first and last seen, the newest trace it was in, the versions it was thrown by (the one it began with first, and the history entry that made that one), what it went up through, whether it was thrown in the browser, and its traces, newest first (the latest 20: when, the version that threw it, the span it was first said in).
The spans of one row of `traceTotals` (`byNameNow`) since `since`: of `kind`, a definition's as named now, each version of it alike (`label` its name now), or, for a page, a view or a statement (no hash), those of that name. Their numbers; each version side by side, newest first, with the entry that made it, and what changed from the one before (and how it runs for it, if that's news); where its calls came from in the browser, as pages waited for them (a server function's); its slowest traces and its latest. Undefined if nothing's recorded.
One definition (or a page or statement, by name) since `since`: each version it has had side by side, newest first as history has them (the one its name points at now marked), each with how it ran and the history entry that made it; each version beside the one before it (what changed, and how it runs for it, if that's news); its slowest calls and newest errors; and where its calls came from in the browser, as the page waited for it. Undefined if nothing's recorded for it.
Of the rows `traceTotals` gave, what runs worse than its version before it (since `since`), and the change that did it: what changed in what it reaches, and the history entry that pointed its name at this version.
What the app spent its time on since `since`, by definition (and kind) as named now, the most time first: calls, errors, p50, p95, the longest and the total. A `client` row is a call as the page waited for it. Each version (hash) is a row of its own, but `byNameNow`: then a definition's earlier versions (`Of.earlier`) are in its row, which says how many versions it holds (and is named as the definition is, the version named now leading, if it ran).
One trace (an id, or the start of one), as a tree: its spans in the order they started, each with its depth (a span whose parent isn't kept here, a caller's, is a root of what this server did) and what it's of; the build that answered; and the jobs it enqueued, each a trace of its own. "none" or "many" if the id names no trace or more than one.