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/chips.js

@@ -19,6 +19,8 @@
  * and Home and End go to its ends. The roving mark is re-applied whenever the set changes, because
  * a Livewire morph rewrites the chips underneath it.
  */
+import { ringIndex } from './util.js'
+
 const CONTROLS = 'button:not(:disabled), a[href]:not([tabindex="-1"]), input:not(:disabled):not([type="hidden"])'
 
 document.addEventListener('alpine:init', () => {
@@ -216,20 +218,9 @@ document.addEventListener('alpine:init', () => {
                 return
             }
 
-            const forwards = getComputedStyle(this.row).direction === 'rtl' ? 'ArrowLeft' : 'ArrowRight'
-            const backwards = forwards === 'ArrowRight' ? 'ArrowLeft' : 'ArrowRight'
-
-            let next = null
-
-            if (event.key === forwards || event.key === 'ArrowDown') {
-                next = (index + 1) % controls.length
-            } else if (event.key === backwards || event.key === 'ArrowUp') {
-                next = (index - 1 + controls.length) % controls.length
-            } else if (event.key === 'Home') {
-                next = 0
-            } else if (event.key === 'End') {
-                next = controls.length - 1
-            }
+            const rtl = getComputedStyle(this.row).direction === 'rtl'
+            // Up and Down move the row too, unmirrored, beside whichever of Left and Right does.
+            const next = ringIndex(event.key, index, controls.length, { rtl }) ?? ringIndex(event.key, index, controls.length, { vertical: true })
 
             if (next === null) {
                 return