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-epg-section.component.html

@@ -9,7 +9,10 @@
         </div>
     </header>
 
-    <div class="setting-item setting-item--full-control">
+    <div
+        class="setting-item setting-item--full-control"
+        data-setting-id="epg-view-mode"
+    >
         <div class="setting-item__meta">
             <h4>{{ 'SETTINGS.EPG_VIEW_MODE' | translate }}</h4>
             <p>{{ 'SETTINGS.EPG_VIEW_MODE_DESCRIPTION' | translate }}</p>
@@ -43,7 +46,10 @@
         </div>
     </div>
 
-    <div class="setting-item setting-item--full-control">
+    <div
+        class="setting-item setting-item--full-control"
+        data-setting-id="epg-offset"
+    >
         <div class="setting-item__meta">
             <h4>{{ 'SETTINGS.EPG_OFFSET_TITLE' | translate }}</h4>
             <p>{{ 'SETTINGS.EPG_OFFSET_HINT' | translate }}</p>
@@ -69,7 +75,10 @@
         </div>
     </div>
 
-    <div class="setting-item setting-item--full-control">
+    <div
+        class="setting-item setting-item--full-control"
+        data-setting-id="epg-sources"
+    >
         <div class="setting-item__meta" data-test-id="epg-source-formats">
             <h4>{{ 'SETTINGS.EPG_SOURCE_LIST_TITLE' | translate }}</h4>
             <p>{{ 'SETTINGS.EPG_SOURCE_FORMATS_HINT' | translate }}</p>
@@ -178,7 +187,7 @@
         </div>
     </div>
 
-    <div class="setting-item">
+    <div class="setting-item" data-setting-id="prefer-uploaded-epg">
         <div class="setting-item__meta">
             <h4>{{ 'SETTINGS.PREFER_UPLOADED_EPG_TITLE' | translate }}</h4>
             <p>{{ 'SETTINGS.PREFER_UPLOADED_EPG_HINT' | translate }}</p>