Add footer with mailto link, version and build date

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

src/globals.d.ts

@@ -0,0 +1,2 @@
+declare const __APP_VERSION__: string;
+declare const __BUILD_DATE__: string;

src/routes/+page.svelte

@@ -81,7 +81,7 @@
 	const latest = $derived(data.at(-1));
 </script>
 
-<main class="min-h-screen bg-gray-950 text-gray-100 p-8">
+<main class="min-h-screen bg-gray-950 text-gray-100 p-8 flex flex-col">
 	<h1 class="text-2xl font-semibold mb-1">Bodenfeuchte</h1>
 	<p class="text-sm text-gray-400 mb-6">
 		Letzte 6 Stunden · Aktualisierung: {lastUpdate || '…'}
@@ -105,4 +105,9 @@
 		{/if}
 		<canvas bind:this={canvas} class={data.length === 0 ? 'hidden' : ''}></canvas>
 	</div>
+
+	<footer class="mt-auto pt-8 flex justify-between text-xs text-gray-600">
+		<a href="mailto:rexfue@gmail.com" class="hover:text-gray-400 transition-colors">rexfue@gmail.com</a>
+		<span>v{__APP_VERSION__} · {__BUILD_DATE__}</span>
+	</footer>
 </main>

vite.config.ts

@@ -1,6 +1,13 @@
 import { sveltekit } from '@sveltejs/kit/vite';
 import { defineConfig } from 'vite';
+import { readFileSync } from 'fs';
+
+const pkg = JSON.parse(readFileSync('./package.json', 'utf-8'));
 
 export default defineConfig({
-	plugins: [sveltekit()]
+	plugins: [sveltekit()],
+	define: {
+		__APP_VERSION__: JSON.stringify(pkg.version),
+		__BUILD_DATE__: JSON.stringify(new Date().toLocaleDateString('de-DE')),
+	}
 });