examples/ferriskey-presentation.json does not pass rustmotion validate (pre-existing on main)

[LeadcodeDev]

A shipped example fails the validation CLAUDE.md declares mandatory.

$ rustmotion validate -f examples/ferriskey-presentation.json
Geometry: 1 violation(s)
ERROR: gradient_text (wrap=false but text too wide)
  view: 0, scene: 4
  path: views[0].scenes[4].children[1].children[1].children[0].children[0]
  bbox: [290, 509] -> [690, 631]   (viewport: 1920x1080)
  axis: x
  hint: gradient_text natural width is 404px but only 400px available

This is not an audit-chantier regression

Established, not assumed:

• The failure reproduces identically — same 404px figure — at c229ec0, before round 3.
• git log main..c229ec0 over the measurement path (intrinsic.rs, renderer/text.rs, gradient_text.rs, renderer/fonts.rs) is empty: the measuring code is identical to main.
• Same for the validator (commands/geometry.rs) and for the example file itself.

The overflow therefore exists on main and predates the whole chantier.

Why it still matters

404px against 400px available — a 1% overflow. The content is almost certainly fine to the eye. But:

1. CLAUDE.md makes it a mandatory rule that every scenario passes validate before being shown. A repository example that fails contradicts the rule the repository teaches.
2. A shipped example is a reference that generators copy. This one shows them a white-space: nowrap inside a box 4px too narrow.

Directions

In order of preference:

1. Fix the example — widen the box by a few pixels, or drop the font-size slightly. It is a gradient_text with white-space: nowrap in a 400px box; making it conform is trivial and makes the example exemplary.
2. While there, check that the natural width measured by GradientTextIntrinsic matches the pixels actually painted. A 1% discrepancy on a single line could also be a measurement defect — in which case the real bug is not in the example. Settle that before editing the JSON, or the symptom gets masked.

Verification

rustmotion validate -f examples/*.json should pass on all 8. Today: 7 of 8.