perf: fix slow page loads and gate performance in CI

- Ship one hashed Tailwind stylesheet instead of two (one render-blocking)
- Compress responses in-app (brotli/gzip, streaming-safe) and precompress
  the node build so local and CI measurements match production
- Validate the Supabase session once per request
- Render the homepage immediately and stream public stats
- Stream a Pokedex's entries with the page instead of fetching after
  hydration, running the rows and count queries in parallel
- Shrink the avatar and offline placeholder images, fix layout shift,
  contrast, link names and missing meta descriptions
- Add Lighthouse CI (mobile + desktop) with score and metric budgets,
  bundle-size budgets in the build tests, and signed-in speed scenarios

src/routes/pokedex/[id]/+page.server.ts

@@ -1,7 +1,11 @@
 import { error, redirect } from '@sveltejs/kit';
 import PokedexRepository from '$lib/repositories/PokedexRepository';
+import { loadCombinedDataPage } from '$lib/services/CombinedDataService';
 import type { PageServerLoad } from './$types';
 
+// Must match the page's itemsPerPage: the box view needs the whole dex in one page.
+const INITIAL_PAGE_SIZE = 9999;
+
 export const load: PageServerLoad = async ({ locals, params }) => {
 	const { safeGetSession, supabase } = locals;
 	const { session, user } = await safeGetSession();
@@ -22,7 +26,22 @@ export const load: PageServerLoad = async ({ locals, params }) => {
 		throw error(404, 'Pokédex not found');
 	}
 
+	// Streamed rather than awaited: the page shell renders straight away and the entries arrive in
+	// the same response, instead of the browser requesting them after hydration. A failure resolves
+	// to null so the page falls back to fetching (and reporting) through the API.
+	const initialCombinedData = loadCombinedDataPage(supabase, user.id, pokedex, {
+		page: 1,
+		limit: INITIAL_PAGE_SIZE,
+		enableForms: pokedex.isFormDex
+	})
+		.then((result) => result.combinedData)
+		.catch((err) => {
+			console.error('Unable to preload combined data', err);
+			return null;
+		});
+
 	return {
-		pokedex
+		pokedex,
+		initialCombinedData
 	};
 };

src/routes/pokedex/[id]/+page.svelte

@@ -502,8 +502,35 @@
 		});
 	}
 
-	// Fetch data whenever pagination controls change (client-side only)
-	$: if (browser && pokedexId) getData({ page: currentPage, perPage: itemsPerPage });
+	// Show data whenever the dex or pagination changes (client-side only). The first page is streamed
+	// from the server load, so it only needs fetching when that failed or the page changes.
+	let shownKey = '';
+	function showPage(
+		id: string,
+		page: number,
+		perPage: number,
+		initial: Promise<CombinedData[] | null> | undefined
+	) {
+		const key = `${id}:${page}:${perPage}`;
+		if (key === shownKey) return;
+		shownKey = key;
+		if (page !== 1 || !initial) {
+			void getData({ page, perPage });
+			return;
+		}
+		combinedData = null;
+		void initial.then((rows) => {
+			if (shownKey !== key) return;
+			if (!rows) {
+				void getData({ page, perPage });
+				return;
+			}
+			combinedData = rows;
+			boxNumbers = calculateBoxNumbers(rows.length);
+		});
+	}
+	$: if (browser && pokedexId)
+		showPage(pokedexId, currentPage, itemsPerPage, data?.initialCombinedData);
 
 	onMount(() => {
 		if (!browser) return;