chore: commit pending changes before custom services implementation

frontend/src/lib/components/admin/ImageUpload.svelte

@@ -4,6 +4,7 @@
 	import FileDropZone from '$lib/components/ui/file-drop-zone.svelte';
 	import { authStore } from '$lib/stores/auth.svelte';
 	import * as AlertDialog from '$lib/components/ui/alert-dialog';
+	import heic2any from 'heic2any';
 
 	// =============== Image Upload ===============
 	let uploading = $state(false);
@@ -28,9 +29,60 @@
 
 	let hasOversizedFiles = $derived(uploadFiles.some(isFileTooBig));
 
-	function handleFilesDropped(files: File[]) {
-		uploadFiles = files;
-		generatePreviews(files);
+	function isHeicFile(file: File): boolean {
+		const name = file.name.toLowerCase();
+		return name.endsWith('.heic') || name.endsWith('.heif');
+	}
+
+	/**
+	 * Check if the browser can natively decode a HEIC file.
+	 * Safari (macOS/iOS) and Chrome-on-Android have native HEIC support,
+	 * which preserves HDR metadata and color profiles better than any conversion.
+	 */
+	function supportsNativeHeicDecode(file: File): Promise<boolean> {
+		return new Promise((resolve) => {
+			const img = new Image();
+			const url = URL.createObjectURL(file);
+			img.onload = () => { URL.revokeObjectURL(url); resolve(true); };
+			img.onerror = () => { URL.revokeObjectURL(url); resolve(false); };
+			img.src = url;
+		});
+	}
+
+	async function convertHeicToPng(file: File): Promise<File> {
+		const result = await heic2any({ blob: file, toType: 'image/png' });
+		const blob = Array.isArray(result) ? result[0] : result;
+		const pngName = file.name.replace(/\.(heic|heif)$/i, '.png');
+		return new File([blob], pngName, { type: 'image/png' });
+	}
+
+	async function handleFilesDropped(files: File[]) {
+		const converted = await Promise.all(
+			files.map(async (file) => {
+				if (!isHeicFile(file)) return file;
+
+				// Try native browser HEIC decode first (Safari, Chrome w/ HEVC)
+				// This preserves HDR metadata & color profiles at full quality
+				try {
+					const nativeOk = await supportsNativeHeicDecode(file);
+					if (nativeOk) return file;
+				} catch {
+					// Fall through to heic2any
+				}
+
+				// Fallback: convert to PNG via heic2any (libheif WASM)
+				// PNG is lossless, libheif handles ICC profiles correctly,
+				// and the downstream canvas pipeline is 8-bit anyway.
+				try {
+					return await convertHeicToPng(file);
+				} catch (e) {
+					console.error('HEIC conversion failed for', file.name, e);
+					return file;
+				}
+			})
+		);
+		uploadFiles = converted;
+		generatePreviews(converted);
 	}
 
 	/** Generate scaled previews for each file */