refactor: update forms and other areas to use new shadcn components (#1115)

Co-authored-by: Elias Schneider <login@eliasschneider.com>
Co-authored-by: ItalyPaleAle <43508+ItalyPaleAle@users.noreply.github.com>
Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

frontend/src/lib/components/ui/field/field-separator.svelte

@@ -0,0 +1,38 @@
+<script lang="ts">
+	import { Separator } from "$lib/components/ui/separator/index.js";
+	import { cn, type WithElementRef } from "$lib/utils/style.js";
+	import type { HTMLAttributes } from "svelte/elements";
+	import type { Snippet } from "svelte";
+
+	let {
+		ref = $bindable(null),
+		class: className,
+		children,
+		...restProps
+	}: WithElementRef<HTMLAttributes<HTMLDivElement>> & {
+		children?: Snippet;
+	} = $props();
+
+	const hasContent = $derived(!!children);
+</script>
+
+<div
+	bind:this={ref}
+	data-slot="field-separator"
+	data-content={hasContent}
+	class={cn(
+		"relative -my-2 h-5 text-sm group-data-[variant=outline]/field-group:-mb-2",
+		className
+	)}
+	{...restProps}
+>
+	<Separator class="absolute inset-0 top-1/2" />
+	{#if children}
+		<span
+			class="bg-background text-muted-foreground relative mx-auto block w-fit px-2"
+			data-slot="field-separator-content"
+		>
+			{@render children()}
+		</span>
+	{/if}
+</div>