feat(fend): skeleton implementation of the form from XML

src/lib/components/fields/DateField.svelte

@@ -0,0 +1,17 @@
+<script lang="ts">
+	import type { DateField } from '$lib/types';
+
+	let { field, value = '', onChange }: { field: DateField; value: string; onChange: (v: string) => void } = $props();
+</script>
+
+<label class="block">
+	<span class="text-sm font-medium">{field.label}</span>
+	<input
+		type="text"
+		{value}
+		placeholder={field.placeholder}
+		oninput={(e) => onChange((e.target as HTMLInputElement).value)}
+		class="mt-1 block w-full rounded px-3 py-2 text-sm"
+		style="background: var(--bg-input); border: 1px solid var(--border); color: var(--text);"
+	/>
+</label>