refactor: move person domain components and utils to lib/person/

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

frontend/src/lib/person/PersonChip.svelte

@@ -0,0 +1,30 @@
+<script lang="ts">
+import { abbreviateName, getInitials, personAvatarColor } from '$lib/utils/personFormat';
+
+type Person = { id: string; firstName?: string | null; lastName: string; displayName: string };
+
+type Props = {
+	person: Person;
+	abbreviated: boolean;
+};
+
+let { person, abbreviated }: Props = $props();
+
+const name = $derived(abbreviated ? abbreviateName(person) : person.displayName);
+const avatarColor = $derived(personAvatarColor(person.id));
+const initials = $derived(getInitials(person.displayName));
+</script>
+
+<a
+	href="/persons/{person.id}"
+	class="inline-flex shrink-0 items-center gap-1.5 rounded-full border border-line bg-muted px-2 py-0.5 hover:border-primary hover:bg-surface focus-visible:ring-2 focus-visible:ring-primary"
+>
+	<span
+		class="flex h-[25px] w-[25px] shrink-0 items-center justify-center rounded-full text-[13px] font-bold text-white"
+		style="background-color: {avatarColor}"
+		aria-hidden="true"
+	>
+		{initials}
+	</span>
+	<span class="text-[14px] font-semibold text-ink">{name}</span>
+</a>