Animate a pottery studio's kilns heating, holding and cooling in one self-contained HTML file

# Animate a pottery studio's kilns heating, holding and cooling in one self-contained HTML file Make a small animated scene: a pottery studio kiln firing curve. Write one file, `out/scene.html`, that works opened straight from disk with no network access. `spec.json` gives the page title, the stage size and the scene parameters. **Looks are not scored**: the page is opened in a headless browser (800x600 window, UTC time zone, network blocked) and checked by objective tests only. ## Scene contract - Draw the scene on one `<canvas>` or `<svg>` stage of `width` x `height` CSS pixels (spec.json), visible on load, with `<title>` containing spec.json `title`. - Animate continuously from load (`requestAnimationFrame` or timers); no click is needed unless stated below. - Expose `window.sceneState()`, returning the scene's current state in stage pixel coordinates (origin top-left of the stage): `{kilns: [{name, x, temp_c, status: "waiting" | "heating" | "holding" | "cooling" | "cooled"}, ...]} (canvas px, y down; one entry per spec.json kiln; x = the kiln's centre; temp_c = the kiln's temperature in degrees C)`. Extra fields are fine. It must describe what is actually drawn. - Time 0 is `performance.now()` 0 (seconds = `performance.now()` / 1000). Each kiln sits at its own `room_c` until its `start_s`; it then heats in a straight line at `ramp_cps` degrees per second starting from `room_c` (not from 0), reaching `peak_c` at start_s + (peak_c - room_c) / ramp_cps; it holds at `peak_c` for `hold_s` seconds; it then cools in a straight line at `cool_cps` degrees per second until it is back at `room_c`, and stays there. Draw each kiln with a temperature bar `px_per_100c` pixels tall per 100 degrees. `sceneState()` must return the state at the moment it is called. - The page must log no errors and throw no exceptions. Keep the file at most 200,000 bytes; no external scripts, fonts, images or URLs (inline everything). ## Checks (partial credit = share passed) 1. `self_contained`: `out/scene.html` exists, is at most 200,000 bytes, references no http(s) or protocol-relative URL, and requests nothing from the network when opened. 2. `has_canvas_or_svg`: a visible `<canvas>` or `<svg>` of at least 300x200 CSS pixels is on the page. 3. `frames_change`: over 3 s, some later screenshot differs from the first in at least 0.1% of pixels, and at least 3 of 30 screenshots differ. 4. `kiln_temperature`: at every sample more than 0.05 s from any of that kiln's phase changes, each kiln's x is within 1.5 px of its spec.json `x` and its temp_c is within 2 degrees of the firing curve: `room_c` before `start_s`, then rising at `ramp_cps` degrees per second from `room_c`, `peak_c` during the hold, falling at `cool_cps` degrees per second, and `room_c` again once cooled. 5. `kiln_status`: at those samples each kiln's `status` is waiting before `start_s`, heating until it reaches `peak_c`, holding for `hold_s` seconds, cooling until it is back at `room_c`, and cooled after that; the samples include heating, holding and cooling. 6. `no_console_errors`: no uncaught exception, `console.error` or browser error is logged during the run. ## How this run works - Work on your own: nobody will answer questions in this task, and writing to `ask/` counts against the run. - Write only under `out/`. Create `out/` if it is missing. Inputs are synthetic; don't fetch anything from the network. - Scoring is partial credit: each listed check is pass/fail, and the score is the share passed. Numbers are compared to within 0.005 unless the task says otherwise.