crowdsim 1.19.0

Every number this tool produces is a curve — rate against latency, per step — and the only place that curve
was ever drawn is the GUI. The moment a result left the page it went back to being a table of eight rows, with
the reader asked to draw the ramp in their head. report now draws it. The interesting half of the work is
what the charts refuse to draw: a chart is the most persuasive thing this tool can produce, and a chart of a
run that measured nothing is the most persuasive wrong answer available to it.

Added

• crowdsim report <run-id> --html: the same run as one self-contained page. The ramp as a curve with
  the SLO and the read timeout drawn on it, the knee as a band between the last clean rate and the first
  crossed one, p95 per class against the limit each class is actually held to, and the cache per layer. One
  file, no dependencies: no script, no font, no stylesheet, nothing fetched — it opens offline, attaches to a
  ticket, and prints to PDF with the tables expanded. Needs node; the markdown report is unchanged and
  still needs nothing but python3.
• An invalid run gets no latency chart, and one chart it does get. generator_ok: false means no step
  measured the rate it claims, and a curve drawn from it looks exactly like a healthy system absorbing load.
  Such a run gets the requested-against-delivered chart — the evidence of why it is invalid — and nothing
  else: no ramp, no per-class bars, not even a p95 tile. Same for a target that never answered: a p95 of
  nearly zero is not a fast system. And a knee recorded next to a verdict that voids it is shown as not
  counting, because an older summary can carry both and the knee is the number that gets quoted in rooms
  this tool is not in.
• A threshold line only where there is a threshold, and one that does not fit is named. A limit line at a
  guessed value moves the knee for the reader, so a run archived before the summary carried its thresholds
  gets a curve with no line and a sentence saying why. A read timeout ten times the p95 is left off the scale
  rather than flattening the curve into the bottom of the picture — and said to be left off, because a line
  that is simply absent reads as a limit nothing came near.
• The rest of the drawing rules, each with a test. A partial step is a hollow marker, a dashed segment and
  a note (the brake fires while latency is climbing, so that step is a fraction of one, biased towards its
  worst part). A cache layer whose header never appeared is unknown, never a 0% bar — that is usually a
  wrong header name in the profile, a different bug with a different fix. A step that emitted no p95 is absent
  rather than plotted at zero. Every chart carries the same numbers as a table underneath it and describes
  itself in words, for a screen reader and for when the SVG does not render at all.
• The summary records the limits the run was judged against: slo.max_p95_ms, slo.max_failed_rate,
  slo.guillotine_ms and slo.per_class. They were already in the generator's context — the brake and the
  knee use them — and the only way the numbers left a run was the sentence in knee.crossed.why. A threshold
  is not something to reconstruct from prose.
• The GUI offers both, by spawning the same command: Report (.md) and Report with charts (.html),
  through GET /api/history/<run-id>/report?format=md|html. Any other format is a 400 — the value ends up in
  an argv.
• Geometry is pure and unit-tested in lib/report-html.mjs + tests/unit/report-html.test.js, with
  coordinates asserted as numbers: that x increases along the ramp, that a higher p95 is a smaller y, that
  the knee band starts on the clean step and ends on the crossed one. A wrong scale throws nothing. The e2e
  suite then draws every run in its archive from real data and checks the rule per run — the first version
  of that check asserted a curve on the newest run, which happened to be the unreachable one, and the suite
  was right to fail.

Changed

• --html reports one run: --html --compare is a usage error (exit 2) naming crowdsim compare. Drawing
  two runs on one pair of axes without that command's refusals would put a confident picture behind two
  different experiments. The markdown report still embeds the comparison, refusal included.
• docs/cli.md carries a real screenshot of the page, taken from a real run against a slow origin on
  loopback. Taking it found a threshold label sitting on top of a data point, which is the reason to take it.

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Container image

docker pull ghcr.io/hiway-media/crowdsim:1.19.0

Install and usage: docs/docker.md