Let the shadows out of the namespace they were reset in

`--shadow-color` sat one line above `--shadow-*: initial`, and a Tailwind
namespace reset clears its own namespace — so the tint never reached the built
CSS, every `rgb(var(--shadow-color) / n%)` became an invalid declaration, and
all three shadows computed to none. Not just the notice pill this task is
about: every raised surface in the app had been drawing flat.

It read correctly at every point you would look. The source declares the token,
`tokens.test.ts` asserts the declaration is there, and `check-tokens.ts` looks
for properties that are read but never defined — this one was defined. The only
way to see it was to grep the bundle or measure a live element.

So `check-tokens.ts` learns the shape: a token declared above a reset that
would wipe it now fails ci, with the line and the fix. The evidence screenshots
are regenerated, and the notice is captured as a padded page region — the
resting shadow is 3% at 3px, and cropping to the element cut off the whole of
what the box is about.