feat: add provider type selector to tracking-configs, use IconGridSelect everywhere

- Tracking Configs: add provider type field (was missing entirely)
- All 4 config pages: provider type uses IconGridSelect during creation,
  shown as read-only text during editing (provider type is immutable)
- Pages: tracking-configs, command-configs, template-configs,
  command-template-configs

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

@@ -13,6 +13,11 @@
 	import ConfirmModal from '$lib/components/ConfirmModal.svelte';
 	import Hint from '$lib/components/Hint.svelte';
 	import IconButton from '$lib/components/IconButton.svelte';
+	import IconGridSelect from '$lib/components/IconGridSelect.svelte';
+
+	const providerTypeItems = [
+		{ value: 'immich', icon: 'mdiCamera', label: 'Immich' },
+	];
 	import { snackSuccess, snackError } from '$lib/stores/snackbar.svelte';
 	import { highlightFromUrl } from '$lib/highlight';
 	import type { TrackingConfig } from '$lib/types';
@@ -98,6 +103,15 @@
 			</div>
 		</div>
 
+		<div>
+			<label class="block text-sm font-medium mb-1">{t('trackingConfig.providerType')}</label>
+			{#if !editing}
+				<IconGridSelect items={providerTypeItems} bind:value={form.provider_type} columns={2} />
+			{:else}
+				<p class="text-sm text-[var(--color-muted-foreground)]">{form.provider_type}</p>
+			{/if}
+		</div>
+
 		<!-- Event tracking -->
 		<fieldset class="border border-[var(--color-border)] rounded-md p-3">
 			<legend class="text-sm font-medium px-1">{t('trackingConfig.eventTracking')}</legend>