Cut duplicated and speculative code across the package

An over-engineering audit of the whole tree, applied in five reviewed
batches. Behaviour stays the same except where UPGRADE.md says otherwise.

PHP: the showcase and error-page stylesheets are prebuilt into
resources/dist by bin/stylesheets.mjs, through Vite's own postcss-import
(first occurrence kept, the order an application's build gives), instead
of Stylesheets::bundle() inlining imports on every request; only the
import walk DesignGuard needs stays. SchemeStylesheet::withProfiles()
replaces three copies of the scheme-plus-profiles loop, material:scheme
leaves spec and contrast checks to the node script that already made
them, and the error page's scheme cache, the hashed view namespace, the
translations path with no lang/ folder and DesignGuard's 1.x-name hints
are gone.

JS: the androidx shape port progress.js and both bin scripts each carried
lives once in resources/js/shapes.js (the generated SVGs are unchanged);
util.js holds ringIndex(), ms(), reopenGuard() and remember(), which
were written out several times; listeners are released through
AbortController; tooltip.js's hoverPopover() serves the rich tooltip too.

CSS: every rule for an element inside the navigation rail queries
`--md-navigation-rail-value` instead of repeating the seven collapsed
conditions under five media branches; badge, alert, progress, slider and
button read one non-inheriting colour-role table (components/color.css);
the dialog chrome, the submenu's popover chrome, the chip's state layer
and touch target, and the visually-hidden inputs use the shared rules
they copied; foundation/tokens.css is folded into foundation.css.

Views: Support\Field and Support\Link replace the error-key, bound-value
and link-attribute blocks copied into the fields and link components;
the timepicker period group, the menu filter and the showcase head are
partials; the datepicker's steppers and entry fields are loops; component
docblocks no longer restate SKILL.md.

Tests and tooling: one dataset-driven ComponentStylesheetsTest replaces
four per-group files, DesignGuardTest and the layout-component tests use
datasets, browser tests share one ready() helper, CSS parsing lives in
ComponentStylesheet alone. docs/audits and the finding IDs citing it are
removed, as are pestphp/pest-plugin-laravel, the unused composer scripts
and check:font; the lint job runs in the feature job, which now installs
node packages so the prebuilt-stylesheet staleness test runs in CI.

Feature suite 1177 passed, Chrome browser suite 299 passed.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

resources/js/layers.js

@@ -85,6 +85,17 @@ document.addEventListener('keydown', (event) => {
     }
 }, true)
 
+/** The nearest layer matching `selector` around `target` that is open, walking out past shut ones. */
+const nearestOpen = (target, selector) => {
+    let layer = target instanceof Element ? target.closest(selector) : null
+
+    while (layer !== null && !isOpen(layer)) {
+        layer = layer.parentElement?.closest(selector) ?? null
+    }
+
+    return layer
+}
+
 /**
  * Whether a `focusin` is an open modal layer moving the focus into itself (see the header): the
  * focus arrives from outside the nearest open layer around its target, or from nowhere, and no Tab
@@ -96,11 +107,7 @@ export const openingFocus = (event) => {
         return false
     }
 
-    let layer = event.target.closest(MODAL_LAYERS)
-
-    while (layer !== null && !isOpen(layer)) {
-        layer = layer.parentElement?.closest(MODAL_LAYERS) ?? null
-    }
+    const layer = nearestOpen(event.target, MODAL_LAYERS)
 
     return layer !== null && !(event.relatedTarget instanceof Node && layer.contains(event.relatedTarget))
 }
@@ -111,11 +118,7 @@ const owns = (panel, event) => {
         return false
     }
 
-    let layer = event.target instanceof Element ? event.target.closest(LAYERS) : null
-
-    while (layer !== null && !isOpen(layer)) {
-        layer = layer.parentElement?.closest(LAYERS) ?? null
-    }
+    const layer = nearestOpen(event.target, LAYERS)
 
     return layer === null ? panels.at(-1) === panel : layer === panel
 }