fix(a11y): address R9 code-review findings (glass shadow, focus dedup)

- #1: remove the 9 dead `shadow-*` from glass surfaces instead of letting them override the tuned glass
  box-shadow. The @layer components move made a JSX shadow-* win AND atomically drop the glass inset
  top-edge highlight; deleting the (always-dead) utilities keeps the intended glass depth incl. the
  inset sheen. Verified in-browser: a .glass box-shadow again includes its inset segment.
- #3: drop the per-element focus-visible outlines from the rail chrome buttons and SavedViews action
  buttons — the global button:focus-visible fallback already draws the identical 2px accent ring, so
  they were redundant. Verified: the pin button rings from the global rule alone.
- #5: unify the focus-within outline offset (offset-2) on the SearchBar and ShareDialog pills.
- #2 (double outline on the pill when an inner button is focused): NOT fixed — the clean fix
  (has-[input:focus] so only the input rings the pill) does not generate under Tailwind v4 (measured:
  no rule emitted). Kept the working focus-within, which is a11y-correct (every element still shows a
  focus indicator); the overlapping ring is an accepted cosmetic edge-case.
- #4 (weak ring on solid-fill selected items): deferred to R10 with the selected-paint tokenisation.

Gate green (tsc/eslint/prettier/knip/vitest 79).

frontend/src/components/SavedViewsWidget.tsx

@@ -288,7 +288,7 @@ function ViewRow({
         {...attributes}
         {...listeners}
         title={t("views.reorder")}
-        className="p-1 text-muted/60 hover:text-muted cursor-grab touch-none shrink-0 rounded-sm outline-hidden focus-visible:outline-2 focus-visible:outline-accent/60"
+        className="p-1 text-muted/60 hover:text-muted cursor-grab touch-none shrink-0"
       >
         <GripVertical className="w-3.5 h-3.5" />
       </button>
@@ -296,7 +296,7 @@ function ViewRow({
         onClick={onApply}
         title={t("views.apply")}
         aria-current={active ? "true" : undefined}
-        className={`flex-1 min-w-0 text-left text-xs py-1 truncate rounded-sm outline-hidden focus-visible:outline-2 focus-visible:outline-accent/60 ${
+        className={`flex-1 min-w-0 text-left text-xs py-1 truncate ${
           active ? "text-accent font-medium" : "text-fg"
         }`}
       >
@@ -306,7 +306,7 @@ function ViewRow({
         <button
           onClick={onToggleDefault}
           title={view.is_default ? t("views.isDefault") : t("views.makeDefault")}
-          className={`p-1 rounded outline-hidden transition focus-visible:outline-2 focus-visible:outline-accent/60 ${
+          className={`p-1 rounded transition ${
             view.is_default
               ? "text-accent"
               : "text-muted opacity-0 group-hover:opacity-100 group-focus-within:opacity-100 hover:text-accent"
@@ -317,21 +317,21 @@ function ViewRow({
         <button
           onClick={onShare}
           title={t("views.share")}
-          className="p-1 rounded-sm text-muted opacity-0 group-hover:opacity-100 group-focus-within:opacity-100 hover:text-fg transition outline-hidden focus-visible:outline-2 focus-visible:outline-accent/60"
+          className="p-1 rounded-sm text-muted opacity-0 group-hover:opacity-100 group-focus-within:opacity-100 hover:text-fg transition"
         >
           <Share2 className="w-3.5 h-3.5" />
         </button>
         <button
           onClick={onStartRename}
           title={t("views.rename")}
-          className="p-1 rounded-sm text-muted opacity-0 group-hover:opacity-100 group-focus-within:opacity-100 hover:text-fg transition outline-hidden focus-visible:outline-2 focus-visible:outline-accent/60"
+          className="p-1 rounded-sm text-muted opacity-0 group-hover:opacity-100 group-focus-within:opacity-100 hover:text-fg transition"
         >
           <Pencil className="w-3.5 h-3.5" />
         </button>
         <button
           onClick={onDelete}
           title={t("views.delete")}
-          className="p-1 rounded-sm text-muted opacity-0 group-hover:opacity-100 group-focus-within:opacity-100 hover:text-red-400 transition outline-hidden focus-visible:outline-2 focus-visible:outline-accent/60"
+          className="p-1 rounded-sm text-muted opacity-0 group-hover:opacity-100 group-focus-within:opacity-100 hover:text-red-400 transition"
         >
           <Trash2 className="w-3.5 h-3.5" />
         </button>