feat: IconGridSelect, CrossLink, SearchPalette components + entity crosslinks

New components:
- IconGridSelect: Visual grid selector replacing <select> dropdowns,
  with icon + label cells, fixed-position popup, smart placement
- CrossLink: Inline clickable badge for cross-entity navigation,
  hover highlights primary, used on entity cards
- SearchPalette: Ctrl+K global command palette, searches all entity
  types via cached data, grouped results, keyboard navigation

Integration:
- Targets: type selector uses IconGridSelect (4-column grid with icons)
- Targets: bot crosslink on telegram/email/matrix target cards
- Command Trackers: provider and config badges → CrossLinks
- Command Trackers: listener bot name → CrossLink
- Command Configs: template config shown as CrossLink on card
- Notification Trackers: provider CrossLink added to card
- Layout: SearchPalette mounted globally

Infrastructure:
- Added CommandConfig, CommandTemplateConfig, CommandTracker types
- Added notificationTrackersCache, commandTrackersCache to caches
- Added allCaches map and fetchAllCaches() for search palette
- Added searchPalette i18n keys (EN/RU)

frontend/src/routes/notification-trackers/+page.svelte

@@ -14,6 +14,7 @@
 	import ConfirmModal from '$lib/components/ConfirmModal.svelte';
 	import Hint from '$lib/components/Hint.svelte';
 	import IconButton from '$lib/components/IconButton.svelte';
+	import CrossLink from '$lib/components/CrossLink.svelte';
 	import { snackSuccess, snackError } from '$lib/stores/snackbar.svelte';
 	import type { Tracker, ServiceProvider, NotificationTarget, TrackingConfig, TemplateConfig } from '$lib/types';
 
@@ -234,6 +235,11 @@
 		return p?.type || '';
 	}
 
+	function getProviderName(id: number): string {
+		const p = providers.find(p => p.id === id);
+		return p?.name || `#${id}`;
+	}
+
 	function configsForTracker(tracker: any, configs: (TrackingConfig | TemplateConfig)[]): any[] {
 		const pt = getProviderType(tracker);
 		return pt ? configs.filter((c: any) => c.provider_type === pt) : configs;
@@ -373,6 +379,7 @@
 							<span class="text-xs px-1.5 py-0.5 rounded {tracker.enabled ? 'bg-[var(--color-success-bg)] text-[var(--color-success-fg)]' : 'bg-[var(--color-muted)] text-[var(--color-muted-foreground)]'}">
 								{tracker.enabled ? t('notificationTracker.active') : t('notificationTracker.paused')}
 							</span>
+t						<CrossLink href="/providers" icon="mdiServer" label={getProviderName(tracker.provider_id)} />
 						</div>
 						<p class="text-sm text-[var(--color-muted-foreground)]">
 							{(tracker.collection_ids || []).length} {t('notificationTracker.albums_count')} · {t('notificationTracker.every')} {tracker.scan_interval}s · {(tracker.tracker_targets || []).length} {t('notificationTracker.linkedTargets')}