feat: add filtering to all entity list pages

- Tracking configs: filter by name + provider type
- Template configs: filter by name + provider type
- Command configs: filter by name + provider type
- Notification trackers: filter by name + provider
- Command trackers: filter by name + provider
- Targets: filter by name (type filtering already existed)
- Nav badge counts include system-owned entities (user_id=0)
- Shows "no items match filter" vs "no items yet" empty states

frontend/src/routes/tracking-configs/+page.svelte

@@ -19,7 +19,13 @@
 	import { highlightFromUrl } from '$lib/highlight';
 	import type { TrackingConfig } from '$lib/types';
 
-	let configs = $derived(trackingConfigsCache.items);
+	let allConfigs = $derived(trackingConfigsCache.items);
+	let filterText = $state('');
+	let filterType = $state('');
+	let configs = $derived(allConfigs.filter(c =>
+		(!filterText || c.name.toLowerCase().includes(filterText.toLowerCase())) &&
+		(!filterType || c.provider_type === filterType)
+	));
 	let loaded = $state(false);
 	let showForm = $state(false);
 	let editing = $state<number | null>(null);
@@ -228,10 +234,28 @@
 </div>
 {/if}
 
-{#if configs.length === 0 && !showForm}
+{#if !showForm && allConfigs.length > 0}
+<div class="flex items-center gap-2 mb-3">
+	<input type="text" bind:value={filterText} placeholder={t('common.filterByName')}
+		class="flex-1 px-3 py-1.5 border border-[var(--color-border)] rounded-md text-sm bg-[var(--color-background)]" />
+	<select bind:value={filterType}
+		class="px-3 py-1.5 border border-[var(--color-border)] rounded-md text-sm bg-[var(--color-background)]">
+		<option value="">{t('common.allTypes')}</option>
+		<option value="immich">Immich</option>
+		<option value="gitea">Gitea</option>
+		<option value="scheduler">Scheduler</option>
+	</select>
+</div>
+{/if}
+
+{#if allConfigs.length === 0 && !showForm}
 	<Card>
 		<EmptyState icon="mdiCog" message={t('trackingConfig.noConfigs')} />
 	</Card>
+{:else if configs.length === 0 && !showForm}
+	<Card>
+		<EmptyState icon="mdiFilterOff" message={t('common.noFilterResults')} />
+	</Card>
 {:else}
 	<div class="space-y-3 stagger-children">
 		{#each configs as config}