feat(settings): search settings from the header and the command palette

The header search on the Settings page was shown but disabled. It now
searches a shared index of all 56 settings rows by translated title,
description and English synonyms, replaces the section page with ranked
results, and opens a result by scrolling to, focusing and briefly
highlighting its row. Enter opens the best match, and the section
navigation shows per-section match counts.

The command palette gains a "Settings" group that lists the best six
matches for a non-empty query, so any setting is one Ctrl/Cmd+K away.
Rows hidden by the current form state fall back to the control that
reveals them; rows the runtime cannot render are never returned.

The index ships through a new @iptvnator/workspace/shell/util/settings-search
sub-entrypoint so it stays out of the eager bundle, and a registry spec
keeps it in step with the section templates.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

apps/web/src/app/settings/settings.component.scss

@@ -114,6 +114,56 @@
     margin-bottom: 0;
 }
 
+// A row opened from settings search or the command palette. It receives
+// programmatic focus (tabindex -1); the highlight is its focus indicator, so
+// the default outline is dropped. The wash fills the row's own padding box
+// and two offset shadows widen it past the flush-left row edges without
+// shifting layout or painting over the separators above and below.
+.setting-item[data-setting-id] {
+    scroll-margin: 96px 0 calc(96px + var(--settings-action-bar-space));
+
+    &:focus {
+        outline: none;
+    }
+}
+
+.setting-item--revealed {
+    --settings-reveal-wash: color-mix(
+        in srgb,
+        var(--app-selection-color) 12%,
+        transparent
+    );
+
+    background: var(--settings-reveal-wash);
+    box-shadow:
+        -12px 0 0 var(--settings-reveal-wash),
+        12px 0 0 var(--settings-reveal-wash);
+    animation: settings-reveal-fade 2.4s ease-out forwards;
+}
+
+@keyframes settings-reveal-fade {
+    0%,
+    60% {
+        background: var(--settings-reveal-wash);
+        box-shadow:
+            -12px 0 0 var(--settings-reveal-wash),
+            12px 0 0 var(--settings-reveal-wash);
+    }
+
+    100% {
+        background: transparent;
+        box-shadow:
+            -12px 0 0 transparent,
+            12px 0 0 transparent;
+    }
+}
+
+@media (prefers-reduced-motion: reduce) {
+    .setting-item--revealed {
+        animation: none;
+    }
+}
+
 .setting-item__meta {
     h4 {
         margin: 0;