style: fix prefer-svelte-reactivity — replace with Svelte reactive equivalents

frontend/src/routes/admin/schedule/+page.svelte

@@ -104,15 +104,15 @@
 	/** Return the current London date as a Date set to midnight in the local timezone.
 	 *  Uses Intl.DateTimeFormat with Europe/London to handle BST/GMT correctly. */
 	function getLondonToday(): Date {
-		const dateStr = new Date().toLocaleDateString('en-CA', { timeZone: 'Europe/London' });
-		return new Date(dateStr + 'T00:00:00');
+		const dateStr = new SvelteDate().toLocaleDateString('en-CA', { timeZone: 'Europe/London' });
+		return new SvelteDate(dateStr + 'T00:00:00');
 	}
 
 	/** Return the current time-of-day in London as minutes since midnight, using
 	 *  Intl.DateTimeFormat with Europe/London so the current-time blue line is
 	 *  positioned correctly regardless of the browser's system timezone. */
 	function getLondonNowMinutes(): number {
-		const timeStr = new Date().toLocaleTimeString('en-GB', {
+		const timeStr = new SvelteDate().toLocaleTimeString('en-GB', {
 			timeZone: 'Europe/London',
 			hour: '2-digit',
 			minute: '2-digit',
@@ -127,7 +127,7 @@
 	 *  at 23:30 UTC (00:30 BST next day) are grouped under the correct
 	 *  London date column rather than the UTC date. */
 	function getLondonDateKey(iso: string): string {
-		return new Date(iso).toLocaleDateString('en-CA', { timeZone: 'Europe/London' });
+		return new SvelteDate(iso).toLocaleDateString('en-CA', { timeZone: 'Europe/London' });
 	}
 
 	function formatWeekLabel(start: Date): string {
@@ -316,7 +316,7 @@
 
 	function navigateWeek(delta: number) {
 		if (!weekStart) return;
-		const d = new Date(weekStart);
+		const d = new SvelteDate(weekStart);
 		d.setDate(d.getDate() + delta * 7);
 		weekStart = d;
 	}

frontend/src/routes/gdpr/+page.svelte

@@ -6,6 +6,7 @@
 	import * as Card from '$lib/components/ui/card';
 	import { Skeleton } from '$lib/components/ui/skeleton';
 	import { Separator } from '$lib/components/ui/separator';
+import { SvelteMap } from 'svelte/reactivity';
 
 	type GdprData = {
 		user_profile: {
@@ -401,7 +402,7 @@
 			.filter((r) => r.status === 'completed')
 			.reduce((sum, r) => sum + Number(r.amount), 0);
 
-		const serviceMap = new Map<string, { count: number; total: number }>();
+		const serviceMap = new SvelteMap<string, { count: number; total: number }>();
 		for (const b of bookings) {
 			for (const s of b.services ?? []) {
 				const existing = serviceMap.get(s.name) ?? { count: 0, total: 0 };
@@ -415,7 +416,7 @@
 			.sort((a, b) => b.count - a.count)
 			.slice(0, 5);
 
-		const methodMap = new Map<string, { count: number; total: number }>();
+		const methodMap = new SvelteMap<string, { count: number; total: number }>();
 		for (const p of payments.filter((p) => p.status === 'completed')) {
 			if (p.payment_method === 'discount') continue;
 			const method = p.payment_method.replace(/_/g, ' ');