A TDZ error blanked the page, and one round of feedback fixed it

The one-shot version rendered nothing, because of a temporal dead zone error:

ReferenceError: Cannot access 'fps' before initialization
    at updateHUD (index.html:535:20)
    at applyPalette (index.html:503:7)

applyPalette() called updateHUD() early in initialisation, and updateHUD() read a variable that a later let fps = … had not declared yet. Worth crediting: the __DEMO_ERROR hook it wrote itself worked correctly and put the stack trace on the page. The error handling was right; the code had a bug.

Then exactly one round of repair, with feedback that was entirely machine-collected — the real stack trace, __DEMO_READY=false, the console error count, and “the frame is black apart from the error box”. Nobody told it what to change. 111 seconds later: __DEMO_READY true, zero page and console errors.

What runs on this page is that repaired version. It introduced two new problems, both left in:

1. The frame is nearly all white. A pale blue haze, with no black hole or disk structure visible — worse exposure than the Astra run.
2. The determinism contract broke. Two renders at the same ?t=7.5 no longer produce the same sha256. The one-shot version was reproducible; fixing the bug damaged either the time lock or the random source.

The particle count is 300,000, the lowest of the three — the other two both report a million. Initialisation takes 25.5 seconds.

Controls: drag to orbit, scroll to zoom, space to pause, 1/2/3 for palettes.